diff --git a/src/main/java/com/fanruan/fs/s3/repository/core/S3ResourceRepository.java b/src/main/java/com/fanruan/fs/s3/repository/core/S3ResourceRepository.java
index 49bd4e6..79b60ca 100644
--- a/src/main/java/com/fanruan/fs/s3/repository/core/S3ResourceRepository.java
+++ b/src/main/java/com/fanruan/fs/s3/repository/core/S3ResourceRepository.java
@@ -28,7 +28,7 @@ import com.fr.workspace.resource.ResourceIOException;
 import java.io.ByteArrayInputStream;
 import java.io.InputStream;
 import java.net.URL;
-import java.nio.charset.Charset;
+import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -163,7 +163,21 @@ public class S3ResourceRepository extends BaseResourceRepository {
 
     @Override
     public void write(String path, byte[] data) {
-        s3.putObject(bucket, path, new String(data, Charset.forName(CHAR_SET)));
+        ObjectMetadata metadata;
+        try {
+            metadata = s3.getObjectMetadata(bucket, path);
+        } catch (Exception e) {
+            metadata = new ObjectMetadata();
+            String mimeType = URLConnection.guessContentTypeFromName(path);
+            if (mimeType != null) {
+                metadata.setContentType(mimeType);
+            }
+            metadata.setContentLength(data.length);
+        }
+        if (metadata != null) {
+            metadata.setContentLength(data.length);
+        }
+        s3.putObject(bucket, path, new ByteArrayInputStream(data), metadata);
     }