diff --git a/application/api/controller/ExpertFieldAi.php b/application/api/controller/ExpertFieldAi.php
new file mode 100644
index 00000000..4ad58f33
--- /dev/null
+++ b/application/api/controller/ExpertFieldAi.php
@@ -0,0 +1,161 @@
+<?php
+
+namespace app\api\controller;
+
+use think\Db;
+use app\common\ExpertFieldAiService;
+
+/**
+ * Expert 领域总结（方案 C - 阶段1：邮箱关联 user.field_ai）
+ *
+ * POST startLinkChain   启动链式队列，批量关联
+ * POST linkOne          同步关联单个 expert_id
+ * POST linkBatch        同步批量关联 expert_ids
+ * POST syncByUser       user 有 field_ai 后，同步到同邮箱 expert
+ * GET  preview          预览是否可关联
+ * GET  statistics       统计 field_ai 覆盖情况
+ */
+class ExpertFieldAi extends Base
+{
+    /**
+     * 启动链式关联队列
+     * Worker: php think queue:work --queue ExpertFieldAi
+     */
+    public function startLinkChain()
+    {
+        $force = intval($this->request->param('force', 0)) === 1;
+        $delay = max(0, intval($this->request->param('delay', 1)));
+
+        $svc = new ExpertFieldAiService();
+        $started = $svc->startLinkChain($force, $delay);
+
+        return jsonSuccess([
+            'started' => $started,
+            'queue'   => ExpertFieldAiService::QUEUE_NAME,
+            'force'   => $force,
+            'msg'     => $started ? 'link chain enqueued' : 'no pending experts',
+        ]);
+    }
+
+    /**
+     * 同步关联单个 expert
+     */
+    public function linkOne()
+    {
+        $expertId = intval($this->request->param('expert_id', 0));
+        $force    = intval($this->request->param('force', 0)) === 1;
+        if ($expertId <= 0) {
+            return jsonError('expert_id required');
+        }
+
+        $svc = new ExpertFieldAiService();
+        $result = $svc->linkFromUser($expertId, $force);
+        if (empty($result['ok'])) {
+            return jsonError(isset($result['error']) ? $result['error'] : 'failed');
+        }
+        return jsonSuccess($result);
+    }
+
+    /**
+     * 同步批量关联
+     * expert_ids: 逗号分隔，或传 limit 扫描待处理前 N 条
+     */
+    public function linkBatch()
+    {
+        $force = intval($this->request->param('force', 0)) === 1;
+        $idsRaw = trim((string)$this->request->param('expert_ids', ''));
+        $limit = min(max(intval($this->request->param('limit', 0)), 0), 200);
+
+        $ids = [];
+        if ($idsRaw !== '') {
+            $ids = array_filter(array_map('intval', explode(',', $idsRaw)));
+        } elseif ($limit > 0) {
+            $ids = Db::name('expert')
+                ->where('state', '<>', 5)
+                ->where(function ($q) {
+                    $q->where('field_ai_status', ExpertFieldAiService::STATUS_PENDING)
+                        ->whereOr('field_ai_status', ExpertFieldAiService::STATUS_FAILED);
+                })
+                ->order('expert_id asc')
+                ->limit($limit)
+                ->column('expert_id');
+        }
+
+        if (empty($ids)) {
+            return jsonError('expert_ids 或 limit 必填');
+        }
+
+        $svc = new ExpertFieldAiService();
+        $result = $svc->batchLinkFromUser($ids, $force);
+        return jsonSuccess($result);
+    }
+
+    /**
+     * user 更新 field_ai 后，同步到同邮箱 expert
+     */
+    public function syncByUser()
+    {
+        $userId = intval($this->request->param('user_id', 0));
+        $force  = intval($this->request->param('force', 0)) === 1;
+        if ($userId <= 0) {
+            return jsonError('user_id required');
+        }
+
+        $svc = new ExpertFieldAiService();
+        $result = $svc->syncExpertsByUserId($userId, $force);
+        if (empty($result['ok'])) {
+            return jsonError(isset($result['error']) ? $result['error'] : 'failed');
+        }
+        return jsonSuccess($result);
+    }
+
+    /**
+     * 预览是否可关联
+     */
+    public function preview()
+    {
+        $expertId = intval($this->request->param('expert_id', 0));
+        if ($expertId <= 0) {
+            return jsonError('expert_id required');
+        }
+
+        $svc = new ExpertFieldAiService();
+        $result = $svc->previewLink($expertId);
+        if (empty($result['ok'])) {
+            return jsonError(isset($result['error']) ? $result['error'] : 'failed');
+        }
+
+        $result['field_ai_status_text'] = $svc->statusLabel(intval($result['expert_field_ai_status']));
+        return jsonSuccess($result);
+    }
+
+    /**
+     * 统计 field_ai 覆盖
+     */
+    public function statistics()
+    {
+        $total = Db::name('expert')->where('state', '<>', 5)->count();
+        $done = Db::name('expert')->where('state', '<>', 5)->where('field_ai_status', ExpertFieldAiService::STATUS_DONE)->count();
+        $userLink = Db::name('expert')
+            ->where('state', '<>', 5)
+            ->where('field_ai_source', ExpertFieldAiService::SOURCE_USER_LINK)
+            ->count();
+        $noUserLink = Db::name('expert')
+            ->where('state', '<>', 5)
+            ->where('field_ai_status', ExpertFieldAiService::STATUS_NO_USER_LINK)
+            ->count();
+        $pending = Db::name('expert')
+            ->where('state', '<>', 5)
+            ->where('field_ai_status', ExpertFieldAiService::STATUS_PENDING)
+            ->count();
+
+        return jsonSuccess([
+            'total'          => $total,
+            'done'           => $done,
+            'user_link'      => $userLink,
+            'no_user_link'   => $noUserLink,
+            'pending'        => $pending,
+            'coverage_rate'  => $total > 0 ? round($done / $total * 100, 2) . '%' : '0%',
+        ]);
+    }
+}
diff --git a/application/api/controller/ExpertManage.php b/application/api/controller/ExpertManage.php
index 87992b2c..bd3a0fea 100644
--- a/application/api/controller/ExpertManage.php
+++ b/application/api/controller/ExpertManage.php
@@ -44,17 +44,22 @@ class ExpertManage extends Base
 
         $query = Db::name('expert')->alias('e');
         $countQuery = Db::name('expert')->alias('e');
-        $needJoin = ($field !== '');
 
-        if ($needJoin) {
-            $query->join('t_expert_field ef', 'ef.expert_id = e.expert_id AND ef.state = 0', 'inner');
-            $countQuery->join('t_expert_field ef', 'ef.expert_id = e.expert_id AND ef.state = 0', 'inner');
-            if ($field !== '') {
-                $query->where('ef.field', 'like', '%' . $field . '%');
-                $countQuery->where('ef.field', 'like', '%' . $field . '%');
-            }
-            $query->group('e.expert_id');
-            $countQuery->group('e.expert_id');
+        if ($field !== '') {
+            $fieldExpertIds = Db::name('expert_field')
+                ->where('state', 0)
+                ->where('field', 'like', '%' . $field . '%')
+                ->column('expert_id');
+            $fieldExpertIds = array_values(array_unique(array_filter(array_map('intval', $fieldExpertIds))));
+
+            $fieldWhere = function ($q) use ($field, $fieldExpertIds) {
+                $q->where('e.field_ai', 'like', '%' . $field . '%');
+                if (!empty($fieldExpertIds)) {
+                    $q->whereOr('e.expert_id', 'in', $fieldExpertIds);
+                }
+            };
+            $query->where($fieldWhere);
+            $countQuery->where($fieldWhere);
         }
 
         if ($state !== '-1' && $state !== '') {
@@ -62,8 +67,8 @@ class ExpertManage extends Base
             $countQuery->where('e.state', intval($state));
         }
         if ($keyword !== '') {
-            $query->where('e.name|e.email|e.affiliation', 'like', '%' . $keyword . '%');
-            $countQuery->where('e.name|e.email|e.affiliation', 'like', '%' . $keyword . '%');
+            $query->where('e.name|e.email|e.affiliation|e.field_ai', 'like', '%' . $keyword . '%');
+            $countQuery->where('e.name|e.email|e.affiliation|e.field_ai', 'like', '%' . $keyword . '%');
         }
         if ($source !== '') {
             $query->where('e.source', $source);
@@ -72,7 +77,7 @@ class ExpertManage extends Base
 
 //        $countQuery = clone $query;
 //        $total = $countQuery->distinct('e.expert_id')->count();
-        $total = $needJoin ? count($countQuery->group('e.expert_id')->column('e.expert_id')) : $countQuery->count();
+        $total = $countQuery->count();
 
         $list = $query
             ->field('e.*')
diff --git a/application/api/job/ExpertFieldAiFill.php b/application/api/job/ExpertFieldAiFill.php
new file mode 100644
index 00000000..d86afe12
--- /dev/null
+++ b/application/api/job/ExpertFieldAiFill.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace app\api\job;
+
+use think\queue\Job;
+use app\common\ExpertFieldAiService;
+
+/**
+ * Expert field_ai 链式任务（阶段1：邮箱关联 user.field_ai）
+ *
+ * data:
+ *   - expert_id
+ *   - queue     队列名，默认 ExpertFieldAi
+ *   - force     1=强制重算
+ *   - mode      link（默认）
+ *
+ * Worker: php think queue:work --queue ExpertFieldAi
+ */
+class ExpertFieldAiFill
+{
+    public function fire(Job $job, $data)
+    {
+        $expertId = isset($data['expert_id']) ? intval($data['expert_id']) : 0;
+        $queue    = isset($data['queue']) ? (string)$data['queue'] : ExpertFieldAiService::QUEUE_NAME;
+        $force    = !empty($data['force']);
+        $mode     = isset($data['mode']) ? (string)$data['mode'] : 'link';
+
+        $svc = new ExpertFieldAiService();
+        if ($expertId > 0 && $mode === 'link') {
+            $svc->linkFromUser($expertId, $force);
+        }
+
+        $job->delete();
+
+        $delay = max(0, (int)(isset($data['delay']) ? $data['delay'] : 1));
+        $svc->enqueueNextLink($delay, $queue, $expertId, $force);
+    }
+}
diff --git a/application/common/ExpertFieldAiService.php b/application/common/ExpertFieldAiService.php
new file mode 100644
index 00000000..eae654d0
--- /dev/null
+++ b/application/common/ExpertFieldAiService.php
@@ -0,0 +1,321 @@
+<?php
+
+namespace app\common;
+
+use think\Db;
+use think\Queue;
+
+/**
+ * Expert 领域总结（方案 C）
+ * 阶段1：通过 email 关联 t_user / t_user_reviewer_info，复用 user.field_ai
+ * 阶段2（后续）：对 field_ai_status=4 的记录走 LLM 总结
+ */
+class ExpertFieldAiService
+{
+    const QUEUE_NAME = 'ExpertFieldAi';
+
+    const STATUS_PENDING = 0;
+    const STATUS_DONE = 1;
+    const STATUS_INSUFFICIENT = 2;
+    const STATUS_FAILED = 3;
+    const STATUS_NO_USER_LINK = 4;
+
+    const SOURCE_USER_LINK = 'user_link';
+    const SOURCE_AI = 'ai';
+
+    private $logFile;
+
+    public function __construct()
+    {
+        $this->logFile = ROOT_PATH . 'runtime' . DS . 'expert_field_ai.log';
+    }
+
+    /**
+     * 启动链式关联（从 expert_id=0 之后找下一位待处理专家）。
+     */
+    public function startLinkChain($force = false, $delay = 1, $queue = '')
+    {
+        return $this->enqueueNextLink($delay, $queue, 0, $force);
+    }
+
+    /**
+     * 链式：处理 expert_id > $afterExpertId 的下一位。
+     */
+    public function enqueueNextLink($delay = 1, $queue = '', $afterExpertId = 0, $force = false)
+    {
+        if ($queue === '') {
+            $queue = self::QUEUE_NAME;
+        }
+        $afterExpertId = intval($afterExpertId);
+        $expertId = $this->findNextLinkExpertId($afterExpertId, $force);
+        if ($expertId <= 0) {
+            $this->log('[ExpertFieldAi] link chain finished after expert_id=' . $afterExpertId);
+            return false;
+        }
+
+        $data = [
+            'expert_id' => $expertId,
+            'queue'     => $queue,
+            'force'     => $force ? 1 : 0,
+            'mode'      => 'link',
+        ];
+        $jobClass = 'app\\api\\job\\ExpertFieldAiFill@fire';
+        if ($delay > 0) {
+            Queue::later($delay, $jobClass, $data, $queue);
+        } else {
+            Queue::push($jobClass, $data, $queue);
+        }
+        $this->log('[ExpertFieldAi] enqueued expert_id=' . $expertId . ' queue=' . $queue);
+        return true;
+    }
+
+    /**
+     * 单个 expert：尝试从 user 邮箱关联 field_ai。
+     *
+     * @return array{ok:bool, linked?:bool, skipped?:bool, field_ai?:string, user_id?:int, error?:string}
+     */
+    public function linkFromUser($expertId, $force = false)
+    {
+        $expertId = intval($expertId);
+        if ($expertId <= 0) {
+            return ['ok' => false, 'error' => 'invalid expert_id'];
+        }
+
+        $expert = Db::name('expert')->where('expert_id', $expertId)->find();
+        if (!$expert) {
+            return ['ok' => false, 'error' => 'expert not found'];
+        }
+
+        if (!$force
+            && intval($expert['field_ai_status']) === self::STATUS_DONE
+            && trim((string)$expert['field_ai']) !== '') {
+            return [
+                'ok'       => true,
+                'skipped'  => true,
+                'field_ai' => (string)$expert['field_ai'],
+                'source'   => (string)($expert['field_ai_source'] ?? ''),
+            ];
+        }
+
+        $email = strtolower(trim((string)($expert['email'] ?? '')));
+        if ($email === '') {
+            $this->updateFieldAi($expertId, '', self::STATUS_NO_USER_LINK, '', 'no email');
+            return ['ok' => true, 'linked' => false, 'reason' => 'empty email'];
+        }
+
+        $user = Db::name('user')
+            ->where('email', $email)
+            ->where('state', 0)
+            ->field('user_id,email,realname')
+            ->find();
+
+        if (!$user) {
+            $this->updateFieldAi($expertId, '', self::STATUS_NO_USER_LINK, '', 'no matching user');
+            return ['ok' => true, 'linked' => false, 'reason' => 'user not found'];
+        }
+
+        $uri = Db::name('user_reviewer_info')
+            ->where('reviewer_id', intval($user['user_id']))
+            ->where('state', 0)
+            ->find();
+
+        $fieldAi = $uri ? trim((string)($uri['field_ai'] ?? '')) : '';
+        $userStatus = $uri ? intval($uri['field_ai_status']) : 0;
+
+        if ($fieldAi === '' || $userStatus !== UserFieldAiService::STATUS_DONE) {
+            $this->updateFieldAi($expertId, '', self::STATUS_NO_USER_LINK, '', 'user field_ai not ready');
+            return [
+                'ok'      => true,
+                'linked'  => false,
+                'user_id' => intval($user['user_id']),
+                'reason'  => 'user has no field_ai',
+            ];
+        }
+
+        $this->updateFieldAi($expertId, $fieldAi, self::STATUS_DONE, self::SOURCE_USER_LINK, 'linked from user_id=' . $user['user_id']);
+        return [
+            'ok'       => true,
+            'linked'   => true,
+            'field_ai' => $fieldAi,
+            'user_id'  => intval($user['user_id']),
+            'source'   => self::SOURCE_USER_LINK,
+        ];
+    }
+
+    /**
+     * 批量同步（同步执行，适合小批量调试）。
+     */
+    public function batchLinkFromUser(array $expertIds, $force = false)
+    {
+        $linked = 0;
+        $skipped = 0;
+        $noLink = 0;
+        $failed = 0;
+        $details = [];
+
+        foreach ($expertIds as $expertId) {
+            $expertId = intval($expertId);
+            if ($expertId <= 0) {
+                continue;
+            }
+            $result = $this->linkFromUser($expertId, $force);
+            if (empty($result['ok'])) {
+                $failed++;
+            } elseif (!empty($result['skipped'])) {
+                $skipped++;
+            } elseif (!empty($result['linked'])) {
+                $linked++;
+            } else {
+                $noLink++;
+            }
+            $details[] = array_merge(['expert_id' => $expertId], $result);
+        }
+
+        return [
+            'total'   => count($details),
+            'linked'  => $linked,
+            'skipped' => $skipped,
+            'no_link' => $noLink,
+            'failed'  => $failed,
+            'details' => $details,
+        ];
+    }
+
+    /**
+     * 预览：expert 是否可关联到 user.field_ai。
+     */
+    public function previewLink($expertId)
+    {
+        $expertId = intval($expertId);
+        $expert = Db::name('expert')->where('expert_id', $expertId)->find();
+        if (!$expert) {
+            return ['ok' => false, 'error' => 'expert not found'];
+        }
+
+        $email = strtolower(trim((string)($expert['email'] ?? '')));
+        $user = null;
+        $uri = null;
+        if ($email !== '') {
+            $user = Db::name('user')->where('email', $email)->where('state', 0)->field('user_id,email,realname')->find();
+            if ($user) {
+                $uri = Db::name('user_reviewer_info')
+                    ->where('reviewer_id', intval($user['user_id']))
+                    ->where('state', 0)
+                    ->find();
+            }
+        }
+
+        $canLink = $user && $uri
+            && trim((string)($uri['field_ai'] ?? '')) !== ''
+            && intval($uri['field_ai_status']) === UserFieldAiService::STATUS_DONE;
+
+        return [
+            'ok'                    => true,
+            'expert_id'             => $expertId,
+            'expert_email'          => $email,
+            'expert_field_ai'       => (string)($expert['field_ai'] ?? ''),
+            'expert_field_ai_status'=> intval($expert['field_ai_status'] ?? 0),
+            'matched_user_id'       => $user ? intval($user['user_id']) : 0,
+            'matched_user_name'     => $user ? (string)$user['realname'] : '',
+            'user_field_ai'         => $uri ? (string)($uri['field_ai'] ?? '') : '',
+            'user_field_ai_status'  => $uri ? intval($uri['field_ai_status']) : 0,
+            'can_link'              => $canLink,
+        ];
+    }
+
+    /**
+     * user 生成 field_ai 后，反向同步到同邮箱 expert（可选调用）。
+     */
+    public function syncExpertsByUserId($userId, $force = false)
+    {
+        $userId = intval($userId);
+        $user = Db::name('user')->where('user_id', $userId)->where('state', 0)->field('user_id,email')->find();
+        if (!$user || trim((string)$user['email']) === '') {
+            return ['ok' => false, 'error' => 'user not found'];
+        }
+
+        $email = strtolower(trim((string)$user['email']));
+        $expertIds = Db::name('expert')
+            ->where('email', $email)
+            ->where('state', '<>', 5)
+            ->column('expert_id');
+
+        if (empty($expertIds)) {
+            return ['ok' => true, 'synced' => 0, 'msg' => 'no expert with same email'];
+        }
+
+        return array_merge(['ok' => true], $this->batchLinkFromUser($expertIds, $force));
+    }
+
+    private function findNextLinkExpertId($afterExpertId, $force)
+    {
+        $batch = 50;
+        $cursor = intval($afterExpertId);
+
+        while (true) {
+            $query = Db::name('expert')
+                ->where('expert_id', '>', $cursor)
+                ->where('state', '<>', 5);
+
+            if (!$force) {
+                $query->where(function ($q) {
+                    $q->where('field_ai_status', self::STATUS_PENDING)
+                        ->whereOr('field_ai_status', self::STATUS_FAILED);
+                });
+            }
+
+            $ids = $query->order('expert_id asc')->limit($batch)->column('expert_id');
+            if (empty($ids)) {
+                return 0;
+            }
+
+            foreach ($ids as $expertId) {
+                $expertId = intval($expertId);
+                $cursor = $expertId;
+
+                if (!$force) {
+                    $row = Db::name('expert')->where('expert_id', $expertId)->field('field_ai,field_ai_status')->find();
+                    if ($row
+                        && intval($row['field_ai_status']) === self::STATUS_DONE
+                        && trim((string)$row['field_ai']) !== '') {
+                        continue;
+                    }
+                }
+
+                return $expertId;
+            }
+        }
+    }
+
+    private function updateFieldAi($expertId, $fieldAi, $status, $source, $note)
+    {
+        $data = [
+            'field_ai'        => mb_substr(trim((string)$fieldAi), 0, 512),
+            'field_ai_status' => intval($status),
+            'field_ai_utime'  => time(),
+            'field_ai_source' => mb_substr(trim((string)$source), 0, 32),
+        ];
+        Db::name('expert')->where('expert_id', intval($expertId))->update($data);
+        if ($note !== '') {
+            $this->log('[ExpertFieldAi] expert_id=' . $expertId . ' status=' . $status . ' note=' . $note);
+        }
+    }
+
+    public function statusLabel($status)
+    {
+        $map = [
+            self::STATUS_PENDING      => 'pending',
+            self::STATUS_DONE         => 'done',
+            self::STATUS_INSUFFICIENT => 'insufficient',
+            self::STATUS_FAILED       => 'failed',
+            self::STATUS_NO_USER_LINK => 'no_user_link',
+        ];
+        return isset($map[$status]) ? $map[$status] : 'unknown';
+    }
+
+    public function log($msg)
+    {
+        $line = date('Y-m-d H:i:s') . ' ' . $msg . PHP_EOL;
+        @file_put_contents($this->logFile, $line, FILE_APPEND);
+    }
+}
diff --git a/application/common/UserFieldAiService.php b/application/common/UserFieldAiService.php
index 3bc023ec..20cee6bc 100644
--- a/application/common/UserFieldAiService.php
+++ b/application/common/UserFieldAiService.php
@@ -102,6 +102,7 @@ class UserFieldAiService
                 throw new Exception('LLM returned empty field');
             }
             $this->updateFieldAi($userId, $fieldAi, self::STATUS_DONE, '');
+            $this->syncLinkedExperts($userId);
             return ['ok' => true, 'field_ai' => $fieldAi];
         } catch (\Throwable $e) {
             $this->updateFieldAi($userId, '', self::STATUS_FAILED, mb_substr($e->getMessage(), 0, 500));
@@ -460,4 +461,17 @@ class UserFieldAiService
         $line = date('Y-m-d H:i:s') . ' ' . $msg . PHP_EOL;
         @file_put_contents($this->logFile, $line, FILE_APPEND);
     }
+
+    /**
+     * user.field_ai 更新后，同步到同邮箱 expert（方案 C 关联）。
+     */
+    private function syncLinkedExperts($userId)
+    {
+        try {
+            $svc = new ExpertFieldAiService();
+            $svc->syncExpertsByUserId(intval($userId), true);
+        } catch (\Throwable $e) {
+            $this->log('[FieldAi] sync expert fail user_id=' . $userId . ' ' . $e->getMessage());
+        }
+    }
 }
diff --git a/sql/add_field_ai_to_expert.sql b/sql/add_field_ai_to_expert.sql
new file mode 100644
index 00000000..0f2b8547
--- /dev/null
+++ b/sql/add_field_ai_to_expert.sql
@@ -0,0 +1,6 @@
+-- Expert 主领域 AI 总结（方案 C：先邮箱关联 user.field_ai，后续可 AI 补全）
+ALTER TABLE `t_expert`
+  ADD COLUMN `field_ai` VARCHAR(512) NOT NULL DEFAULT '' COMMENT 'AI/关联总结的主要研究领域(中文)' AFTER `affiliation`,
+  ADD COLUMN `field_ai_status` TINYINT NOT NULL DEFAULT 0 COMMENT '0待处理 1已生成 2资料不足 3失败 4无user关联待AI' AFTER `field_ai`,
+  ADD COLUMN `field_ai_utime` INT NOT NULL DEFAULT 0 COMMENT 'field_ai 更新时间' AFTER `field_ai_status`,
+  ADD COLUMN `field_ai_source` VARCHAR(32) NOT NULL DEFAULT '' COMMENT '来源: user_link / ai' AFTER `field_ai_utime`;