diff --git a/.env.example b/.env.example
index e69de29..fe8ef84 100644
--- a/.env.example
+++ b/.env.example
@@ -0,0 +1,11 @@
+O_S3_ACCESS_KEY_ID=you_old_access
+O_S3_SECRET_ACCESS_KEY=***
+O_S3_REGION=us-east-1
+O_S3_BUCKET_NAME=resources
+O_S3_ENDPOINT=http://localhost:9000
+
+S3_ACCESS_KEY_ID=access_key
+S3_SECRET_ACCESS_KEY=secret_key
+S3_REGION=cn-shanghai
+S3_BUCKET_NAME=envision
+S3_ENDPOINT=https://tos-s3-cn-shanghai.volces.com
\ No newline at end of file
diff --git a/package.json b/package.json
index 6742c91..44c0494 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
   "description": "",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "migrate": "tsx src/copy.ts"
   },
   "keywords": [],
   "author": "",
@@ -15,4 +15,4 @@
     "@types/node": "^25.2.1",
     "dotenv": "^17.2.4"
   }
-}
+}
\ No newline at end of file
diff --git a/src/copy.ts b/src/copy.ts
index 10d4436..5cdac8c 100644
--- a/src/copy.ts
+++ b/src/copy.ts
@@ -1,4 +1,4 @@
-import { S3Client, ListObjectsV2Command, GetBucketMetadataConfigurationCommand, HeadObjectCommand, CopyObjectCommand } from '@aws-sdk/client-s3';
+import { S3Client, ListObjectsV2Command, HeadObjectCommand, PutObjectCommand, GetObjectCommand } from '@aws-sdk/client-s3';
 import dotenv from 'dotenv';
 dotenv.config();
 
@@ -21,6 +21,156 @@ const newS3Client = new S3Client({
   },
 });
 
-const copyS3Object = async () => {
-  //
-}
\ No newline at end of file
+/**
+ * Get object metadata (ETag) from a bucket
+ */
+const getObjectMetadata = async (client: S3Client, bucket: string, key: string): Promise<{ exists: boolean; etag?: string }> => {
+  try {
+    const response = await client.send(
+      new HeadObjectCommand({
+        Bucket: bucket,
+        Key: key,
+      })
+    );
+    return { exists: true, etag: response.ETag?.replace(/"/g, '') };
+  } catch (error: any) {
+    if (error.name === 'NotFound' || error.$metadata?.httpStatusCode === 404) {
+      return { exists: false };
+    }
+    throw error;
+  }
+};
+
+/**
+ * Copy a single object from source to destination
+ */
+const copyObject = async (key: string): Promise<void> => {
+  const sourceBucket = process.env.O_S3_BUCKET_NAME!;
+  const destBucket = process.env.S3_BUCKET_NAME!;
+
+  console.log(`Copying: ${key}`);
+
+  // Get object from source
+  const getObjectResponse = await oldS3Client.send(
+    new GetObjectCommand({
+      Bucket: sourceBucket,
+      Key: key,
+    })
+  );
+
+  // Convert stream to buffer
+  const bodyBytes = await getObjectResponse.Body?.transformToByteArray();
+  if (!bodyBytes) {
+    throw new Error(`Failed to read object: ${key}`);
+  }
+
+  // Put object to destination
+  await newS3Client.send(
+    new PutObjectCommand({
+      Bucket: destBucket,
+      Key: key,
+      Body: bodyBytes,
+      ContentType: getObjectResponse.ContentType,
+      ContentEncoding: getObjectResponse.ContentEncoding,
+      Metadata: getObjectResponse.Metadata,
+    })
+  );
+
+  console.log(`✓ Copied: ${key}`);
+};
+
+/**
+ * List all objects in source bucket
+ */
+const listAllObjects = async (): Promise<string[]> => {
+  const objects: string[] = [];
+  let continuationToken: string | undefined = undefined;
+  const sourceBucket = process.env.O_S3_BUCKET_NAME!;
+
+  do {
+    const response = await oldS3Client.send(
+      new ListObjectsV2Command({
+        Bucket: sourceBucket,
+        ContinuationToken: continuationToken,
+      })
+    ) as { Contents?: Array<{ Key?: string }>; NextContinuationToken?: string };
+
+    if (response.Contents) {
+      for (const object of response.Contents) {
+        if (object.Key) {
+          objects.push(object.Key);
+        }
+      }
+    }
+
+    continuationToken = response.NextContinuationToken;
+  } while (continuationToken);
+
+  return objects;
+};
+
+/**
+ * Main migration function - copy objects from source to destination
+ * Compares ETags: if different, copy again; if same, skip
+ */
+const copyS3Object = async (): Promise<void> => {
+  console.log('Starting S3 migration...');
+  console.log(`Source: ${process.env.O_S3_ENDPOINT}/${process.env.O_S3_BUCKET_NAME}`);
+  console.log(`Destination: ${process.env.S3_ENDPOINT}/${process.env.S3_BUCKET_NAME}`);
+  console.log('');
+
+  const objects = await listAllObjects();
+  console.log(`Found ${objects.length} objects in source bucket`);
+
+  let copiedCount = 0;
+  let skippedCount = 0;
+  let updatedCount = 0;
+  let errorCount = 0;
+  const sourceBucket = process.env.O_S3_BUCKET_NAME!;
+  const destBucket = process.env.S3_BUCKET_NAME!;
+
+  for (const key of objects) {
+    try {
+      const sourceMeta = await getObjectMetadata(oldS3Client, sourceBucket, key);
+      const destMeta = await getObjectMetadata(newS3Client, destBucket, key);
+
+      if (!destMeta.exists) {
+        // Destination doesn't exist, copy it
+        await copyObject(key);
+        copiedCount++;
+      } else if (sourceMeta.etag !== destMeta.etag) {
+        // ETags differ, update the file
+        console.log(`Updating (ETag changed): ${key}`);
+        console.log(`  Source ETag: ${sourceMeta.etag}`);
+        console.log(`  Dest ETag:   ${destMeta.etag}`);
+        await copyObject(key);
+        updatedCount++;
+      } else {
+        // Same ETag, skip
+        console.log(`- Skip (same ETag): ${key}`);
+        skippedCount++;
+      }
+    } catch (error: any) {
+      console.error(`✗ Error copying ${key}:`, error.message);
+      errorCount++;
+    }
+  }
+
+  console.log('');
+  console.log('Migration complete!');
+  console.log(`Total objects: ${objects.length}`);
+  console.log(`Copied (new): ${copiedCount}`);
+  console.log(`Updated (ETag changed): ${updatedCount}`);
+  console.log(`Skipped (same): ${skippedCount}`);
+  console.log(`Errors: ${errorCount}`);
+};
+
+// Run if this file is executed directly
+if (require.main === module) {
+  copyS3Object().catch((error) => {
+    console.error('Migration failed:', error);
+    process.exit(1);
+  });
+}
+
+export { copyS3Object };
\ No newline at end of file