diff --git a/src/api/queries/keys.ts b/src/api/queries/keys.ts
index ba1fd8b..ddc8679 100644
--- a/src/api/queries/keys.ts
+++ b/src/api/queries/keys.ts
@@ -20,13 +20,7 @@ const campKeys = {
   dashboard: (id: number) => ['camps', 'detail', id, 'dashboard'] as const,
 }
 
-const iconKeys = {
-  all: ['icons'] as const,
-  user: (id: string) => ['icons', 'user', id] as const,
-}
-
 export const qk = {
   me: meKeys,
   camps: campKeys,
-  icons: iconKeys,
 }
diff --git a/src/components/generic/UserIcon.vue b/src/components/generic/UserIcon.vue
index 5b57bad..ef64088 100644
--- a/src/components/generic/UserIcon.vue
+++ b/src/components/generic/UserIcon.vue
@@ -1,86 +1,45 @@
 <script setup lang="ts">
-import { computed, ref, useAttrs } from 'vue'
-import { useQuery } from '@tanstack/vue-query'
-import { qk } from '@/api/queries/keys'
+import { computed, ref } from 'vue'
 import { useUserStore } from '@/store'
 
-const props = defineProps<{ id?: string; size: number; idTooltip?: boolean }>()
-// idTooltip ... クリック時に Tooltip で ID を表示するかどうか
-const userId = props.id ?? useUserStore().user.id // id が指定されていない場合は自分のアイコンを表示
+const props = defineProps<{
+  id?: string
+  size: number
+  /** クリック時に Tooltip で ID を表示 */
+  idTooltip?: boolean
+}>()
 
-const attrs = useAttrs()
 const iconRef = ref<HTMLElement | undefined>()
 
-const imageStyle = {
-  width: `${props.size}px`,
-  height: `${props.size}px`,
-  objectFit: 'contain' as const,
-  borderRadius: '50%',
-  display: 'block',
-  cursor: props.idTooltip ? 'pointer' : 'default',
-}
-
-const directUrl = `https://q.trap.jp/api/v3/public/icon/${userId}`
-
-const {
-  data: cachedIconUrl,
-  isLoading,
-  isFetching,
-  isError,
-} = useQuery<string, Error>({
-  queryKey: qk.icons.user(userId),
-  staleTime: 24 * 60 * 60_000, // 24h
-  gcTime: 24 * 60 * 60_000, // 24h
-  retry: 0,
-  // データURLで保存する
-  queryFn: async () => {
-    const res = await fetch(directUrl)
-    if (!res.ok) throw new Error(`アイコンを取得できませんでした: ${res.status}`)
-
-    const blob = await res.blob()
-    const dataUrl = await new Promise<string>((resolve, reject) => {
-      const reader = new FileReader()
-      reader.onloadend = () => resolve(reader.result as string)
-      reader.onerror = () => reject(new Error('アイコンの変換に失敗しました'))
-      reader.readAsDataURL(blob)
-    })
-    return dataUrl
-  },
-})
-
-const showSkeleton = computed(
-  () => !cachedIconUrl.value || isLoading.value || isFetching.value || isError.value,
-)
-
-const tooltipText = `@${userId}`
+const userId = computed(() => props.id ?? useUserStore().user.id)
+const iconUrl = computed(() => `https://q.trap.jp/api/v3/public/icon/${userId.value}`)
+const cursorStyle = computed(() => ({ cursor: props.idTooltip ? 'pointer' : 'default' }))
 </script>
+
 <template>
-  <template v-if="showSkeleton">
-    <v-avatar :size="size">
-      <v-skeleton-loader type="image" class="w-100 h-100" />
+  <div class="rounded-circle overflow-hidden">
+    <v-avatar ref="iconRef" :size="size" class="d-block" :style="cursorStyle">
+      <v-img :src="iconUrl" :alt="`${userId}のアイコン`" cover :transition="false">
+        <template #placeholder>
+          <v-skeleton-loader type="image" class="w-100 h-100" />
+        </template>
+        <template #error>
+          <v-skeleton-loader type="image" class="w-100 h-100" />
+        </template>
+      </v-img>
     </v-avatar>
-  </template>
-
-  <template v-else>
-    <img
-      ref="iconRef"
-      tabindex="0"
-      v-bind="attrs"
-      :style="imageStyle"
-      :src="cachedIconUrl"
-      loading="lazy"
-    />
 
     <v-tooltip
+      v-if="idTooltip"
       :activator="iconRef"
-      :open-on-hover="idTooltip"
-      :open-on-click="idTooltip"
+      open-on-hover
+      open-on-click
       :open-delay="1000"
       location="top"
     >
-      <span class="text-white font-weight-medium">{{ tooltipText }}</span>
+      <span class="text-white font-weight-medium">{{ `@${userId}` }}</span>
     </v-tooltip>
-  </template>
+  </div>
 </template>
 
 <style module>
diff --git a/vite.config.ts b/vite.config.ts
index 909d555..9efa6b0 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -80,6 +80,22 @@ export default defineConfig(({ mode }) => {
           disableDevLogs: true, // workbox のログを無効化
           globPatterns: ['**/*.{js,css,html,svg,png,jpg,webp,woff2}'],
           navigateFallbackDenylist: [/^\/api/, /^\/login/],
+          runtimeCaching: [
+            {
+              urlPattern: /^https:\/\/q\.trap\.jp\/api\/v3\/public\/icon\/.*/,
+              handler: 'CacheFirst',
+              options: {
+                cacheName: 'user-icons',
+                expiration: {
+                  maxEntries: 200,
+                  maxAgeSeconds: 7 * 24 * 60 * 60, // 1 週間
+                },
+                cacheableResponse: {
+                  statuses: [200],
+                },
+              },
+            },
+          ],
         },
         devOptions: { enabled: true },
       }),