diff --git a/src/database/repositories/dataImporter/index.ts b/src/database/repositories/dataImporter/index.ts
index 67d4c610476e5..d41a0e0045315 100644
--- a/src/database/repositories/dataImporter/index.ts
+++ b/src/database/repositories/dataImporter/index.ts
@@ -14,6 +14,7 @@ import {
 import { LobeChatDatabase } from '@/database/type';
 import { ImportResult } from '@/services/config';
 import { ImporterEntryData } from '@/types/importer';
+import { sanitizeUTF8 } from '@/utils/sanitizeUTF8';
 
 export class DataImporterRepos {
   private userId: string;
@@ -204,9 +205,10 @@ export class DataImporterRepos {
         // 2. insert messages
         if (shouldInsertMessages.length > 0) {
           const inertValues = shouldInsertMessages.map(
-            ({ id, extra, createdAt, updatedAt, sessionId, topicId, ...res }) => ({
+            ({ id, extra, createdAt, updatedAt, sessionId, topicId, content, ...res }) => ({
               ...res,
               clientId: id,
+              content: sanitizeUTF8(content),
               createdAt: new Date(createdAt),
               model: extra?.fromModel,
               parentId: null,
diff --git a/src/libs/langchain/loaders/pdf/index.ts b/src/libs/langchain/loaders/pdf/index.ts
index 2ba2641602a32..f35054243ee00 100644
--- a/src/libs/langchain/loaders/pdf/index.ts
+++ b/src/libs/langchain/loaders/pdf/index.ts
@@ -1,7 +1,7 @@
 import { PDFLoader } from '@langchain/community/document_loaders/fs/pdf';
 
 export const PdfLoader = async (fileBlob: Blob) => {
-  const loader = new PDFLoader(fileBlob);
+  const loader = new PDFLoader(fileBlob, { splitPages: true });
 
   return await loader.load();
 };
diff --git a/src/server/routers/async/file.ts b/src/server/routers/async/file.ts
index e67621b4d26a1..dc6e639722d0c 100644
--- a/src/server/routers/async/file.ts
+++ b/src/server/routers/async/file.ts
@@ -24,6 +24,7 @@ import {
   IAsyncTaskError,
 } from '@/types/asyncTask';
 import { safeParseJSON } from '@/utils/safeParseJSON';
+import { sanitizeUTF8 } from '@/utils/sanitizeUTF8';
 
 const fileProcedure = asyncAuthedProcedure.use(async (opts) => {
   const { ctx } = opts;
@@ -95,16 +96,13 @@ export const fileRouter = router({
                   ctx.jwtPayload,
                 );
 
-                const number = index + 1;
-                console.log(`执行第 ${number} 个任务`);
+                console.log(`run embedding task ${index + 1}`);
 
-                console.time(`任务[${number}]: embeddings`);
                 const embeddings = await agentRuntime.embeddings({
                   dimensions: 1024,
                   input: chunks.map((c) => c.text),
                   model,
                 });
-                console.timeEnd(`任务[${number}]: embeddings`);
 
                 const items: NewEmbeddingsItem[] =
                   embeddings?.map((e, idx) => ({
@@ -114,9 +112,7 @@ export const fileRouter = router({
                     model,
                   })) || [];
 
-                console.time(`任务[${number}]: insert db`);
                 await ctx.embeddingModel.bulkCreate(items);
-                console.timeEnd(`任务[${number}]: insert db`);
               },
               { concurrency: CONCURRENCY },
             );
@@ -215,7 +211,11 @@ export const fileRouter = router({
 
           // after finish partition, we need to filter out some elements
           const chunks = chunkResult.chunks.map(
-            (item): NewChunkItem => ({ ...item, userId: ctx.userId }),
+            ({ text, ...item }): NewChunkItem => ({
+              ...item,
+              text: text ? sanitizeUTF8(text) : '',
+              userId: ctx.userId,
+            }),
           );
 
           const duration = Date.now() - startAt;
diff --git a/src/utils/sanitizeUTF8.test.ts b/src/utils/sanitizeUTF8.test.ts
new file mode 100644
index 0000000000000..39e30c223e488
--- /dev/null
+++ b/src/utils/sanitizeUTF8.test.ts
@@ -0,0 +1,23 @@
+import { sanitizeUTF8 } from './sanitizeUTF8';
+
+describe('UTF-8 Sanitization', () => {
+  it('should handle null bytes', () => {
+    const input = 'test\u0000string';
+    expect(sanitizeUTF8(input)).toBe('teststring');
+  });
+
+  it('should handle invalid UTF-8 sequences', () => {
+    const input = 'test\uD800string'; // 未配对的代理项
+    expect(sanitizeUTF8(input)).toBe('teststring');
+  });
+
+  it('should handle invalid UTF-8 content', () => {
+    const input = '\u0002\u0000\u0000\u0002�{\\"error\\":{\\"code\\":\\"resource_exhausted\\",';
+    expect(sanitizeUTF8(input)).toBe('{\\"error\\":{\\"code\\":\\"resource_exhausted\\",');
+  });
+
+  it('should preserve valid UTF-8 characters', () => {
+    const input = '你好，世界！';
+    expect(sanitizeUTF8(input)).toBe('你好，世界！');
+  });
+});
diff --git a/src/utils/sanitizeUTF8.ts b/src/utils/sanitizeUTF8.ts
new file mode 100644
index 0000000000000..bed8adfc43d53
--- /dev/null
+++ b/src/utils/sanitizeUTF8.ts
@@ -0,0 +1,14 @@
+/**
+ * Sanitize UTF-8 string to remove all control characters and invalid code points.
+ * @param str
+ */
+export const sanitizeUTF8 = (str: string) => {
+  // 移除替换字符 (0xFFFD) 和其他非法字符
+  return (
+    str
+      .replaceAll('�', '') // 移除 Unicode 替换字符
+      // eslint-disable-next-line no-control-regex
+      .replaceAll(/[\u0000-\u0008\u000B\u000C\u000E-\u001F\u007F-\u009F]/g, '') // 移除控制字符
+      .replaceAll(/[\uD800-\uDFFF]/g, '')
+  ); // 移除未配对的代理项码点
+};