diff --git a/src/api.ts b/src/api.ts
index b307536..21a51c0 100644
--- a/src/api.ts
+++ b/src/api.ts
@@ -1,6 +1,6 @@
 import axios from "axios"
 import { router } from "./router"
-import type { TutorialIn, ChallengeIn, FlagType, SubmissionOut, PromptMessage } from "./utils/type"
+import type { TutorialIn, ChallengeIn, FlagType, SubmissionOut, PromptMessage, TaskStatsOut } from "./utils/type"
 import { BASE_URL, STORAGE_KEY } from "./utils/const"
 
 const http = axios.create({
@@ -221,6 +221,13 @@ export const Submission = {
     return res.data as { nominated: boolean }
   },
 
+  async getStats(taskId: number, classname?: string): Promise<TaskStatsOut> {
+    const params: Record<string, string | number> = {}
+    if (classname) params.classname = classname
+    const res = await http.get(`/submission/stats/${taskId}`, { params })
+    return res.data as TaskStatsOut
+  },
+
 }
 
 export const Prompt = {
diff --git a/src/components/Task.vue b/src/components/Task.vue
index 34a956e..8b729f6 100644
--- a/src/components/Task.vue
+++ b/src/components/Task.vue
@@ -38,6 +38,13 @@
         </template>
       </n-flex>
       <n-flex>
+        <n-button
+          v-if="(roleAdmin || roleSuper) && taskTab === TASK_TYPE.Challenge && taskId > 0"
+          text
+          @click="statsModal = true"
+        >
+          <Icon :width="16" icon="lucide:bar-chart-2"></Icon>
+        </n-button>
         <n-button
         v-if="authed"
           text
@@ -56,21 +63,24 @@
     <Tutorial v-if="taskTab === TASK_TYPE.Tutorial" ref="tutorialRef" />
     <Challenge v-else />
   </div>
+  <TaskStatsModal v-model:show="statsModal" :task-id="taskId" />
 </template>
 <script lang="ts" setup>
 import { Icon } from "@iconify/vue"
 import { computed, onMounted, ref } from "vue"
 import { step } from "../store/tutorial"
-import { authed, roleSuper } from "../store/user"
-import { taskTab, challengeDisplay } from "../store/task"
+import { authed, roleAdmin, roleSuper } from "../store/user"
+import { taskTab, taskId, challengeDisplay } from "../store/task"
 import { useRoute, useRouter } from "vue-router"
 import { TASK_TYPE } from "../utils/const"
 import Challenge from "./Challenge.vue"
 import Tutorial from "./Tutorial.vue"
+import TaskStatsModal from "./TaskStatsModal.vue"
 
 const route = useRoute()
 const router = useRouter()
 const tutorialRef = ref<InstanceType<typeof Tutorial>>()
+const statsModal = ref(false)
 
 defineEmits(["hide"])
 
diff --git a/src/components/TaskStatsModal.vue b/src/components/TaskStatsModal.vue
new file mode 100644
index 0000000..79a9de1
--- /dev/null
+++ b/src/components/TaskStatsModal.vue
@@ -0,0 +1,291 @@
+<template>
+  <n-modal
+    :show="show"
+    @update:show="$emit('update:show', $event)"
+    preset="card"
+    title="提交统计"
+    style="max-width: 660px"
+    :bordered="false"
+  >
+    <div style="max-height: 75vh; overflow-y: auto">
+      <template v-if="loading">
+        <n-flex justify="center" style="padding: 40px">
+          <n-spin size="large" />
+        </n-flex>
+      </template>
+
+      <template v-else-if="stats">
+        <!-- 班级筛选 -->
+        <n-flex align="center" style="margin-bottom: 16px; flex-wrap: wrap; gap: 6px">
+          <span style="color: #666; font-size: 12px">班级筛选：</span>
+          <n-button
+            size="small"
+            :type="selectedClass === null ? 'primary' : 'default'"
+            @click="selectClass(null)"
+          >全部</n-button>
+          <n-button
+            v-for="c in stats.classes"
+            :key="c"
+            size="small"
+            :type="selectedClass === c ? 'primary' : 'default'"
+            @click="selectClass(c)"
+          >{{ c }}</n-button>
+        </n-flex>
+
+        <!-- 关键指标 -->
+        <div style="display: grid; grid-template-columns: repeat(5, 1fr); border: 1px solid #eee; border-radius: 6px; overflow: hidden; margin-bottom: 12px">
+          <div
+            v-for="(metric, i) in metrics"
+            :key="metric.label"
+            :style="{
+              padding: '12px 8px',
+              textAlign: 'center',
+              borderRight: i < metrics.length - 1 ? '1px solid #eee' : 'none',
+            }"
+          >
+            <div :style="{ fontSize: '20px', fontWeight: '700', color: metric.color }">{{ metric.value }}</div>
+            <div style="color: #888; font-size: 11px; margin-top: 2px">{{ metric.label }}</div>
+          </div>
+        </div>
+
+        <!-- 未提交名单（可折叠） -->
+        <div style="border: 1px solid #eee; border-radius: 6px; margin-bottom: 8px; overflow: hidden">
+          <div
+            style="padding: 10px 14px; display: flex; align-items: center; justify-content: space-between; cursor: pointer; background: #fff8f8"
+            @click="showUnsubmitted = !showUnsubmitted"
+          >
+            <n-flex align="center" :size="6">
+              <span style="width: 7px; height: 7px; background: #d03050; border-radius: 50%; display: inline-block"></span>
+              <span style="font-weight: 600; color: #d03050; font-size: 12px">未提交（{{ stats.unsubmitted_count }}人）</span>
+            </n-flex>
+            <Icon :icon="showUnsubmitted ? 'lucide:chevron-down' : 'lucide:chevron-right'" :width="14" style="color: #aaa" />
+          </div>
+          <div v-if="showUnsubmitted" style="padding: 10px 14px; background: #fff8f8; display: flex; flex-wrap: wrap; gap: 5px">
+            <n-tag
+              v-for="u in stats.unsubmitted_users"
+              :key="u.username"
+              size="small"
+              :bordered="true"
+              style="border-color: #ffd0d0; background: #fff"
+            >{{ u.username }} <span style="color: #bbb; margin-left: 4px">{{ u.classname }}</span></n-tag>
+            <span v-if="!stats.unsubmitted_users.length" style="color: #aaa; font-size: 12px">暂无</span>
+          </div>
+        </div>
+
+        <!-- 未打分名单（可折叠） -->
+        <div style="border: 1px solid #eee; border-radius: 6px; margin-bottom: 12px; overflow: hidden">
+          <div
+            style="padding: 10px 14px; display: flex; align-items: center; justify-content: space-between; cursor: pointer; background: #fff8f8"
+            @click="showUnrated = !showUnrated"
+          >
+            <n-flex align="center" :size="6">
+              <span style="width: 7px; height: 7px; background: #d03050; border-radius: 50%; display: inline-block"></span>
+              <span style="font-weight: 600; color: #d03050; font-size: 12px">未打分（{{ stats.unrated_count }}人）</span>
+              <span style="font-size: 11px; color: #aaa">— 还没给任何提交打过分</span>
+            </n-flex>
+            <Icon :icon="showUnrated ? 'lucide:chevron-down' : 'lucide:chevron-right'" :width="14" style="color: #aaa" />
+          </div>
+          <div v-if="showUnrated" style="padding: 10px 14px; background: #fff8f8; display: flex; flex-wrap: wrap; gap: 5px">
+            <n-tag
+              v-for="u in stats.unrated_users"
+              :key="u.username"
+              size="small"
+              :bordered="true"
+              style="border-color: #ffd0d0; background: #fff"
+            >{{ u.username }} <span style="color: #bbb; margin-left: 4px">{{ u.classname }}</span></n-tag>
+            <span v-if="!stats.unrated_users.length" style="color: #aaa; font-size: 12px">暂无</span>
+          </div>
+        </div>
+
+        <!-- 提交次数分布 -->
+        <div style="margin-bottom: 12px">
+          <div style="font-weight: 600; font-size: 13px; margin-bottom: 8px; color: #333">
+            提交次数分布
+            <span style="font-size: 11px; color: #aaa; font-weight: 400">（已提交的 {{ stats.submitted_count }} 人）</span>
+          </div>
+          <div style="display: flex; gap: 8px">
+            <div
+              v-for="bucket in countBuckets"
+              :key="bucket.label"
+              :style="{ flex: 1, border: `1px solid ${bucket.borderColor}`, borderRadius: '6px', padding: '10px 8px', textAlign: 'center', background: bucket.bg }"
+            >
+              <div :style="{ fontSize: '20px', fontWeight: '700', color: bucket.color }">{{ bucket.value }}</div>
+              <div style="color: #aaa; font-size: 11px; margin-top: 2px">{{ bucket.label }}</div>
+              <div style="margin-top: 8px; background: #e8e8e8; border-radius: 3px; height: 4px">
+                <div :style="{ background: bucket.color, height: '4px', borderRadius: '3px', width: bucketPct(bucket.value) }"></div>
+              </div>
+              <div style="color: #bbb; font-size: 10px; margin-top: 3px">{{ bucketPct(bucket.value) }}</div>
+            </div>
+          </div>
+        </div>
+
+        <!-- 分数分布 -->
+        <div style="margin-bottom: 12px">
+          <div style="font-weight: 600; font-size: 13px; margin-bottom: 8px; color: #333">
+            分数分布
+            <span style="font-size: 11px; color: #aaa; font-weight: 400">（1–5 星，已打分提交）</span>
+          </div>
+          <div style="display: flex; align-items: flex-end; gap: 6px; height: 80px">
+            <div
+              v-for="bar in scoreBars"
+              :key="bar.label"
+              style="flex: 1; display: flex; flex-direction: column; align-items: center"
+            >
+              <div style="color: #aaa; font-size: 11px; margin-bottom: 3px">{{ bar.value }}</div>
+              <div :style="{ background: bar.color, width: '100%', height: bar.height, borderRadius: '3px 3px 0 0', minHeight: '3px' }"></div>
+              <div style="color: #aaa; font-size: 11px; margin-top: 4px">{{ bar.label }}</div>
+            </div>
+          </div>
+        </div>
+
+        <!-- 人气提交 Top 5 -->
+        <div style="margin-bottom: 12px">
+          <div style="font-weight: 600; font-size: 13px; margin-bottom: 8px; color: #333">
+            人气提交 Top 5
+            <span style="font-size: 11px; color: #aaa; font-weight: 400">（按打分人数）</span>
+          </div>
+          <div style="display: flex; flex-direction: column; gap: 5px">
+            <div
+              v-for="(sub, i) in stats.top_submissions"
+              :key="sub.submission_id"
+              style="display: flex; align-items: center; gap: 10px; padding: 6px 10px; background: #f8f8f8; border-radius: 6px; cursor: pointer"
+              @click="viewSubmission(sub.submission_id)"
+            >
+              <div
+                :style="{ width: '20px', height: '20px', background: rankColor(i), borderRadius: '50%', display: 'flex', alignItems: 'center', justifyContent: 'center', color: '#fff', fontWeight: '700', fontSize: '11px', flexShrink: 0 }"
+              >{{ i + 1 }}</div>
+              <div style="flex: 1">
+                <div style="font-weight: 500; font-size: 13px">{{ sub.username }}</div>
+                <div style="color: #aaa; font-size: 11px">{{ sub.score.toFixed(1) }} 分 · {{ sub.rating_count }} 人打分 · {{ sub.classname }}</div>
+              </div>
+              <div style="color: #2080f0; font-size: 12px">查看 →</div>
+            </div>
+            <span v-if="!stats.top_submissions.length" style="color: #aaa; font-size: 12px">暂无打分记录</span>
+          </div>
+        </div>
+
+        <!-- 标记统计 -->
+        <div>
+          <div style="font-weight: 600; font-size: 13px; margin-bottom: 8px; color: #333">标记统计</div>
+          <n-flex :size="8" style="flex-wrap: wrap">
+            <div
+              v-for="flag in flagBadges"
+              :key="flag.label"
+              :style="{ display: 'flex', alignItems: 'center', gap: '6px', padding: '4px 10px', background: flag.bg, borderRadius: '4px', border: `1px solid ${flag.border}` }"
+            >
+              <span :style="{ width: '7px', height: '7px', background: flag.color, borderRadius: '50%', display: 'inline-block' }"></span>
+              <span :style="{ color: flag.color, fontSize: '12px' }">{{ flag.label }}</span>
+              <span style="font-weight: 700; font-size: 13px; color: #333">{{ flag.value }}</span>
+            </div>
+          </n-flex>
+        </div>
+      </template>
+    </div>
+  </n-modal>
+</template>
+
+<script lang="ts" setup>
+import { ref, computed, watch } from "vue"
+import { Icon } from "@iconify/vue"
+import { useRouter } from "vue-router"
+import { Submission } from "../api"
+import type { TaskStatsOut } from "../utils/type"
+
+const props = defineProps<{ taskId: number; show: boolean }>()
+const emit = defineEmits<{ (e: "update:show", v: boolean): void }>()
+
+const router = useRouter()
+const stats = ref<TaskStatsOut | null>(null)
+const loading = ref(false)
+const selectedClass = ref<string | null>(null)
+const showUnsubmitted = ref(true)
+const showUnrated = ref(true)
+
+async function load(classname?: string) {
+  loading.value = true
+  try {
+    stats.value = await Submission.getStats(props.taskId, classname)
+  } finally {
+    loading.value = false
+  }
+}
+
+function selectClass(c: string | null) {
+  selectedClass.value = c
+  load(c ?? undefined)
+}
+
+function viewSubmission(id: string) {
+  const { href } = router.resolve({ name: "submission", params: { id } })
+  window.open(href, "_blank")
+}
+
+function rankColor(i: number) {
+  return (["#f0a020", "#aaa", "#cd7f32", "#ddd", "#ddd"] as const)[i] ?? "#ddd"
+}
+
+function bucketPct(value: number) {
+  const total = stats.value?.submitted_count ?? 0
+  if (!total) return "0%"
+  return Math.round((value / total) * 100) + "%"
+}
+
+const metrics = computed(() => {
+  if (!stats.value) return []
+  return [
+    { label: "已提交", value: stats.value.submitted_count, color: "#18a058" },
+    { label: "未提交", value: stats.value.unsubmitted_count, color: "#d03050" },
+    { label: "平均分", value: stats.value.average_score?.toFixed(1) ?? "—", color: "#2080f0" },
+    { label: "未打分", value: stats.value.unrated_count, color: "#d03050" },
+    { label: "参与排名", value: stats.value.nominated_count, color: "#f0a020" },
+  ]
+})
+
+const countBuckets = computed(() => {
+  if (!stats.value) return []
+  const d = stats.value.submission_count_distribution
+  return [
+    { label: "仅 1 次", value: d.count_1, color: "#888", bg: "#fafafa", borderColor: "#e0e0e0" },
+    { label: "2 次", value: d.count_2, color: "#2080f0", bg: "#f0f7ff", borderColor: "#d0e8ff" },
+    { label: "3 次", value: d.count_3, color: "#18a058", bg: "#f0fff4", borderColor: "#c8e8d0" },
+    { label: "4 次+", value: d.count_4_plus, color: "#f0a020", bg: "#fffbf0", borderColor: "#ffe0a0" },
+  ]
+})
+
+const scoreBars = computed(() => {
+  if (!stats.value) return []
+  const d = stats.value.score_distribution
+  const vals = [d.range_1_2, d.range_2_3, d.range_3_4, d.range_4_5, d.range_5]
+  const max = Math.max(...vals, 1)
+  const colors = ["#d03050", "#f0a020", "#2080f0", "#18a058", "#18a058"]
+  const labels = ["★", "★★", "★★★", "★★★★", "★★★★★"]
+  return vals.map((v, i) => ({
+    value: v,
+    label: labels[i],
+    color: colors[i],
+    height: Math.max(Math.round((v / max) * 68), 3) + "px",
+  }))
+})
+
+const flagBadges = computed(() => {
+  if (!stats.value) return []
+  const f = stats.value.flag_stats
+  return [
+    { label: "值得展示", value: f.red, color: "#d03050", bg: "#fff0f0", border: "#ffd0d0" },
+    { label: "需要讲解", value: f.blue, color: "#2080f0", bg: "#f0f7ff", border: "#c8deff" },
+    { label: "优秀作品", value: f.green, color: "#18a058", bg: "#f0fff4", border: "#b8e8c8" },
+    { label: "需要改进", value: f.yellow, color: "#f0a020", bg: "#fffbf0", border: "#ffe8a0" },
+  ]
+})
+
+// Load when modal opens
+watch(
+  () => props.show,
+  (val) => {
+    if (val && props.taskId) {
+      selectedClass.value = null
+      load()
+    }
+  },
+)
+</script>
diff --git a/src/pages/Submission.vue b/src/pages/Submission.vue
index 5edda0c..e7dca6d 100644
--- a/src/pages/Submission.vue
+++ b/src/pages/Submission.vue
@@ -43,6 +43,8 @@ onMounted(init)
 </template>
 <style scoped>
 .iframe {
+  position: fixed;
+  inset: 0;
   width: 100%;
   height: 100%;
   border: none;
diff --git a/src/utils/type.ts b/src/utils/type.ts
index 142ab0b..6be28d0 100644
--- a/src/utils/type.ts
+++ b/src/utils/type.ts
@@ -101,3 +101,53 @@ export interface SubmissionAll {
   created: Date
   modified: Date
 }
+
+export interface UserTag {
+  username: string
+  classname: string
+}
+
+export interface TopSubmission {
+  submission_id: string
+  username: string
+  classname: string
+  score: number
+  rating_count: number
+}
+
+export interface SubmissionCountBucket {
+  count_1: number
+  count_2: number
+  count_3: number
+  count_4_plus: number
+}
+
+export interface ScoreBucket {
+  range_1_2: number
+  range_2_3: number
+  range_3_4: number
+  range_4_5: number
+  range_5: number
+}
+
+export interface FlagStats {
+  red: number
+  blue: number
+  green: number
+  yellow: number
+}
+
+export interface TaskStatsOut {
+  submitted_count: number
+  unsubmitted_count: number
+  average_score: number | null
+  unrated_count: number
+  nominated_count: number
+  unsubmitted_users: UserTag[]
+  unrated_users: UserTag[]
+  submission_count_distribution: SubmissionCountBucket
+  score_distribution: ScoreBucket
+  top_submissions: TopSubmission[]
+  flag_stats: FlagStats
+  classes: string[]
+}