diff --git a/src/pages/add-team/add-team.vue b/src/pages/add-team/add-team.vue
index 22fffe1..7febf2c 100644
--- a/src/pages/add-team/add-team.vue
+++ b/src/pages/add-team/add-team.vue
@@ -119,6 +119,15 @@ export default {
           list = res
         }
 
+        // Deduplicate by id
+        const seen = new Set()
+        list = list.filter(item => {
+          const key = item.id
+          if (seen.has(key)) return false
+          seen.add(key)
+          return true
+        })
+        
         this.playerList = list.map(item => ({
           id: item.id,
           name: item.name || item.playerName
diff --git a/src/pages/event-register/event-register.vue b/src/pages/event-register/event-register.vue
index 623a2ad..2245721 100644
--- a/src/pages/event-register/event-register.vue
+++ b/src/pages/event-register/event-register.vue
@@ -66,13 +66,16 @@
         </view>
 
         <view class="player-list">
-          <view class="player-item" v-for="(item, index) in teamList" :key="index">
+          <view class="player-item" v-for="(item, index) in teamList" :key="index" :class="{ 'registered': item.hasRegistered }">
             <view class="player-checkbox" @click="toggleTeam(item)">
               <image v-if="item.selected" class="checkbox-img" src="/static/images/选中@3x.png" mode="aspectFit"></image>
               <image v-else class="checkbox-img" src="/static/images/未选中@3x.png" mode="aspectFit"></image>
             </view>
             <view class="player-info">
-              <view class="player-name">{{ item.name }}</view>
+              <view class="player-name">
+                {{ item.name }}
+                <text v-if="item.hasRegistered" class="registered-tag">已报名</text>
+              </view>
               <view class="player-id">成员数：{{ item.memberCount || 0 }}人</view>
             </view>
             <view class="player-actions">
@@ -482,12 +485,43 @@ export default {
         })
 
         let list = res.records || (Array.isArray(res) ? res : [])
-        this.teamList = list.map(item => ({
-          id: item.id,
-          name: item.teamName || item.name,
-          memberCount: item.memberCount || 0,
-          selected: false
-        }))
+        
+        // Deduplicate by id
+        const seen = new Set()
+        list = list.filter(item => {
+          const key = item.id
+          if (seen.has(key)) return false
+          seen.add(key)
+          return true
+        })
+        
+        // Get current project IDs
+        const projectIds = this.selectedProjects.map(p => p.id)
+        
+        // Check which teams have already registered for these projects
+        let registeredTeamNames = []
+        if (projectIds.length > 0 && this.eventId) {
+          try {
+            const regRes = await athleteAPI.getRegisteredAthletes({
+              competitionId: this.eventId,
+              projectIds: projectIds.join(',')
+            })
+            registeredTeamNames = (regRes || []).filter(r => r.teamName).map(r => r.teamName)
+          } catch (e) {
+            console.log('查询已报名集体失败:', e)
+          }
+        }
+        
+        this.teamList = list.map(item => {
+          const teamName = item.teamName || item.name
+          return {
+            id: item.id,
+            name: teamName,
+            memberCount: item.memberCount || 0,
+            selected: false,
+            hasRegistered: registeredTeamNames.includes(teamName)
+          }
+        })
       } catch (err) {
         console.error('加载集体列表失败:', err)
         this.teamList = []
@@ -530,6 +564,17 @@ export default {
     },
 
     toggleTeam(item) {
+      // Warn if team has already registered for this project
+      if (item.hasRegistered && !item.selected) {
+        uni.showModal({
+          title: '提示',
+          content: '该集体已报名此项目，重复报名将被系统拒绝',
+          confirmText: '知道了',
+          showCancel: false
+        })
+        return
+      }
+      
       const index = this.teamList.findIndex(t => t.id === item.id)
       if (index !== -1) {
         this.$set(this.teamList[index], 'selected', !this.teamList[index].selected)