diff --git a/src/lib/components/organisms/Category/File.svelte b/src/lib/components/organisms/Category/File.svelte
index 23465c1..7d49cf3 100644
--- a/src/lib/components/organisms/Category/File.svelte
+++ b/src/lib/components/organisms/Category/File.svelte
@@ -2,7 +2,6 @@
   import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { DirectoryEntryLabel } from "$lib/components/molecules";
-  import { getFileThumbnail } from "$lib/modules/file";
   import type { FileInfo } from "$lib/modules/filesystem";
   import { requestFileThumbnailDownload, type SelectedFile } from "./service";
 
@@ -34,10 +33,7 @@
 
   $effect(() => {
     if ($info?.dataKey) {
-      getFileThumbnail($info.id)
-        .then(
-          (thumbnailUrl) => thumbnailUrl || requestFileThumbnailDownload($info.id, $info.dataKey!),
-        )
+      requestFileThumbnailDownload($info.id, $info.dataKey)
         .then((thumbnailUrl) => {
           thumbnail = thumbnailUrl ?? undefined;
         })
diff --git a/src/lib/modules/file/cache.ts b/src/lib/modules/file/cache.ts
index fe3c66c..31eac28 100644
--- a/src/lib/modules/file/cache.ts
+++ b/src/lib/modules/file/cache.ts
@@ -1,12 +1,15 @@
+import { LRUCache } from "lru-cache";
 import {
   getFileCacheIndex as getFileCacheIndexFromIndexedDB,
   storeFileCacheIndex,
   deleteFileCacheIndex,
   type FileCacheIndex,
 } from "$lib/indexedDB";
-import { readFile, writeFile, deleteFile } from "$lib/modules/opfs";
+import { readFile, writeFile, deleteFile, deleteDirectory } from "$lib/modules/opfs";
+import { getThumbnailUrl } from "$lib/modules/thumbnail";
 
 const fileCacheIndex = new Map<number, FileCacheIndex>();
+const loadedThumbnails = new LRUCache<number, string>({ max: 100 });
 
 export const prepareFileCache = async () => {
   for (const cache of await getFileCacheIndexFromIndexedDB()) {
@@ -48,3 +51,32 @@ export const deleteFileCache = async (fileId: number) => {
   await deleteFile(`/cache/${fileId}`);
   await deleteFileCacheIndex(fileId);
 };
+
+export const getFileThumbnailCache = async (fileId: number) => {
+  const thumbnail = loadedThumbnails.get(fileId);
+  if (thumbnail) {
+    return thumbnail;
+  }
+
+  const thumbnailBuffer = await readFile(`/thumbnail/file/${fileId}`);
+  if (!thumbnailBuffer) return null;
+
+  const thumbnailUrl = getThumbnailUrl(thumbnailBuffer);
+  loadedThumbnails.set(fileId, thumbnailUrl);
+  return thumbnailUrl;
+};
+
+export const storeFileThumbnailCache = async (fileId: number, thumbnailBuffer: ArrayBuffer) => {
+  await writeFile(`/thumbnail/file/${fileId}`, thumbnailBuffer);
+  loadedThumbnails.set(fileId, getThumbnailUrl(thumbnailBuffer));
+};
+
+export const deleteFileThumbnailCache = async (fileId: number) => {
+  loadedThumbnails.delete(fileId);
+  await deleteFile(`/thumbnail/file/${fileId}`);
+};
+
+export const deleteAllFileThumbnailCaches = async () => {
+  loadedThumbnails.clear();
+  await deleteDirectory("/thumbnail/file");
+};
diff --git a/src/lib/modules/file/index.ts b/src/lib/modules/file/index.ts
index dc708ac..42a5613 100644
--- a/src/lib/modules/file/index.ts
+++ b/src/lib/modules/file/index.ts
@@ -1,4 +1,3 @@
 export * from "./cache";
 export * from "./download";
-export * from "./thumbnail";
 export * from "./upload";
diff --git a/src/lib/modules/file/thumbnail.ts b/src/lib/modules/file/thumbnail.ts
deleted file mode 100644
index 6757ffc..0000000
--- a/src/lib/modules/file/thumbnail.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-import { LRUCache } from "lru-cache";
-import { readFile, writeFile, deleteFile, deleteDirectory } from "$lib/modules/opfs";
-import { getThumbnailUrl } from "$lib/modules/thumbnail";
-
-const loadedThumbnails = new LRUCache<number, string>({ max: 100 });
-
-export const getFileThumbnail = async (fileId: number) => {
-  const thumbnail = loadedThumbnails.get(fileId);
-  if (thumbnail) {
-    return thumbnail;
-  }
-
-  const thumbnailBuffer = await readFile(`/thumbnails/${fileId}`);
-  if (!thumbnailBuffer) return null;
-
-  const thumbnailUrl = getThumbnailUrl(thumbnailBuffer);
-  loadedThumbnails.set(fileId, thumbnailUrl);
-  return thumbnailUrl;
-};
-
-export const storeFileThumbnail = async (fileId: number, thumbnailBuffer: ArrayBuffer) => {
-  await writeFile(`/thumbnails/${fileId}`, thumbnailBuffer);
-  loadedThumbnails.set(fileId, getThumbnailUrl(thumbnailBuffer));
-};
-
-export const deleteFileThumbnail = async (fileId: number) => {
-  loadedThumbnails.delete(fileId);
-  await deleteFile(`/thumbnails/${fileId}`);
-};
-
-export const deleteAllFileThumbnails = async () => {
-  loadedThumbnails.clear();
-  await deleteDirectory("/thumbnails");
-};
diff --git a/src/lib/services/file.ts b/src/lib/services/file.ts
index 57a0749..1a95538 100644
--- a/src/lib/services/file.ts
+++ b/src/lib/services/file.ts
@@ -1,6 +1,12 @@
 import { callGetApi } from "$lib/hooks";
 import { decryptData } from "$lib/modules/crypto";
-import { getFileCache, storeFileCache, downloadFile, storeFileThumbnail } from "$lib/modules/file";
+import {
+  getFileCache,
+  storeFileCache,
+  getFileThumbnailCache,
+  storeFileThumbnailCache,
+  downloadFile,
+} from "$lib/modules/file";
 import { getThumbnailUrl } from "$lib/modules/thumbnail";
 import type { FileThumbnailInfoResponse } from "$lib/server/schemas";
 
@@ -18,6 +24,9 @@ export const requestFileDownload = async (
 };
 
 export const requestFileThumbnailDownload = async (fileId: number, dataKey: CryptoKey) => {
+  const cache = await getFileThumbnailCache(fileId);
+  if (cache) return cache;
+
   let res = await callGetApi(`/api/file/${fileId}/thumbnail`);
   if (!res.ok) return null;
 
@@ -29,6 +38,6 @@ export const requestFileThumbnailDownload = async (fileId: number, dataKey: Cryp
   const thumbnailEncrypted = await res.arrayBuffer();
   const thumbnail = await decryptData(thumbnailEncrypted, thumbnailEncryptedIv, dataKey);
 
-  storeFileThumbnail(fileId, thumbnail); // Intended
+  storeFileThumbnailCache(fileId, thumbnail); // Intended
   return getThumbnailUrl(thumbnail);
 };
diff --git a/src/routes/(fullscreen)/settings/thumbnails/+page.svelte b/src/routes/(fullscreen)/settings/thumbnails/+page.svelte
index a498f1c..68c6d6f 100644
--- a/src/routes/(fullscreen)/settings/thumbnails/+page.svelte
+++ b/src/routes/(fullscreen)/settings/thumbnails/+page.svelte
@@ -4,7 +4,7 @@
   import { goto } from "$app/navigation";
   import { BottomDiv, Button, FullscreenDiv } from "$lib/components/atoms";
   import { IconEntryButton, TopBar } from "$lib/components/molecules";
-  import { deleteAllFileThumbnails } from "$lib/modules/file";
+  import { deleteAllFileThumbnailCaches } from "$lib/modules/file";
   import { getFileInfo } from "$lib/modules/filesystem";
   import { masterKeyStore } from "$lib/stores";
   import File from "./File.svelte";
@@ -44,7 +44,7 @@
 <FullscreenDiv class="bg-gray-100 !px-0">
   <div class="flex flex-grow flex-col space-y-4">
     <div class="flex-shrink-0 bg-white p-4 !pt-0">
-      <IconEntryButton icon={IconDelete} onclick={deleteAllFileThumbnails} class="w-full">
+      <IconEntryButton icon={IconDelete} onclick={deleteAllFileThumbnailCaches} class="w-full">
         저장된 썸네일 모두 삭제하기
       </IconEntryButton>
     </div>
diff --git a/src/routes/(fullscreen)/settings/thumbnails/+page.ts b/src/routes/(fullscreen)/settings/thumbnails/+page.ts
index 3fc7cff..a16cb8e 100644
--- a/src/routes/(fullscreen)/settings/thumbnails/+page.ts
+++ b/src/routes/(fullscreen)/settings/thumbnails/+page.ts
@@ -1,6 +1,6 @@
 import { error } from "@sveltejs/kit";
 import { callPostApi } from "$lib/hooks";
-import type { MissingThumbnailFileScanResponse } from "$lib/server/schemas/file";
+import type { MissingThumbnailFileScanResponse } from "$lib/server/schemas";
 import type { PageLoad } from "./$types";
 
 export const load: PageLoad = async ({ fetch }) => {
diff --git a/src/routes/(fullscreen)/settings/thumbnails/service.svelte.ts b/src/routes/(fullscreen)/settings/thumbnails/service.svelte.ts
index a3f77ce..4e430d5 100644
--- a/src/routes/(fullscreen)/settings/thumbnails/service.svelte.ts
+++ b/src/routes/(fullscreen)/settings/thumbnails/service.svelte.ts
@@ -1,7 +1,7 @@
 import { limitFunction } from "p-limit";
 import { get, writable, type Writable } from "svelte/store";
 import { encryptData } from "$lib/modules/crypto";
-import { storeFileThumbnail } from "$lib/modules/file";
+import { storeFileThumbnailCache } from "$lib/modules/file";
 import type { FileInfo } from "$lib/modules/filesystem";
 import { generateImageThumbnail, generateVideoThumbnail } from "$lib/modules/thumbnail";
 import type { FileThumbnailUploadRequest } from "$lib/server/schemas";
@@ -104,7 +104,7 @@ const requestThumbnailUpload = limitFunction(
     workingFiles.delete(fileId);
     persistentStates.files = persistentStates.files.filter(({ id }) => id != fileId);
 
-    storeFileThumbnail(fileId, thumbnail.plaintext); // Intended
+    storeFileThumbnailCache(fileId, thumbnail.plaintext); // Intended
     return true;
   },
   { concurrency: 4 },
diff --git a/src/routes/(main)/directory/[[id]]/DirectoryEntries/File.svelte b/src/routes/(main)/directory/[[id]]/DirectoryEntries/File.svelte
index 4245898..8251331 100644
--- a/src/routes/(main)/directory/[[id]]/DirectoryEntries/File.svelte
+++ b/src/routes/(main)/directory/[[id]]/DirectoryEntries/File.svelte
@@ -2,7 +2,6 @@
   import type { Writable } from "svelte/store";
   import { ActionEntryButton } from "$lib/components/atoms";
   import { DirectoryEntryLabel } from "$lib/components/molecules";
-  import { getFileThumbnail } from "$lib/modules/file";
   import type { FileInfo } from "$lib/modules/filesystem";
   import { formatDateTime } from "$lib/modules/util";
   import { requestFileThumbnailDownload } from "./service";
@@ -36,10 +35,7 @@
 
   $effect(() => {
     if ($info?.dataKey) {
-      getFileThumbnail($info.id)
-        .then(
-          (thumbnailUrl) => thumbnailUrl || requestFileThumbnailDownload($info.id, $info.dataKey!),
-        )
+      requestFileThumbnailDownload($info.id, $info.dataKey)
         .then((thumbnailUrl) => {
           thumbnail = thumbnailUrl ?? undefined;
         })
diff --git a/src/routes/(main)/directory/[[id]]/service.svelte.ts b/src/routes/(main)/directory/[[id]]/service.svelte.ts
index b29630a..ba5fc4a 100644
--- a/src/routes/(main)/directory/[[id]]/service.svelte.ts
+++ b/src/routes/(main)/directory/[[id]]/service.svelte.ts
@@ -5,8 +5,8 @@ import { generateDataKey, wrapDataKey, unwrapHmacSecret, encryptString } from "$
 import {
   storeFileCache,
   deleteFileCache,
-  storeFileThumbnail,
-  deleteFileThumbnail,
+  storeFileThumbnailCache,
+  deleteFileThumbnailCache,
   uploadFile,
 } from "$lib/modules/file";
 import type {
@@ -88,7 +88,7 @@ export const requestFileUpload = async (
 
   storeFileCache(res.fileId, res.fileBuffer); // Intended
   if (res.thumbnailBuffer) {
-    storeFileThumbnail(res.fileId, res.thumbnailBuffer); // Intended
+    storeFileThumbnailCache(res.fileId, res.thumbnailBuffer); // Intended
   }
 
   return true;
@@ -121,11 +121,11 @@ export const requestEntryDeletion = async (entry: SelectedEntry) => {
   if (entry.type === "directory") {
     const { deletedFiles }: DirectoryDeleteResponse = await res.json();
     await Promise.all(
-      deletedFiles.flatMap((fileId) => [deleteFileCache(fileId), deleteFileThumbnail(fileId)]),
+      deletedFiles.flatMap((fileId) => [deleteFileCache(fileId), deleteFileThumbnailCache(fileId)]),
     );
     return true;
   } else {
-    await Promise.all([deleteFileCache(entry.id), deleteFileThumbnail(entry.id)]);
+    await Promise.all([deleteFileCache(entry.id), deleteFileThumbnailCache(entry.id)]);
     return true;
   }
 };