diff --git a/source/src/main/java/one/nem/lacerta/source/file/impl/FileManagerImpl.java b/source/src/main/java/one/nem/lacerta/source/file/impl/FileManagerImpl.java
index 559c41de..5a8ffa64 100644
--- a/source/src/main/java/one/nem/lacerta/source/file/impl/FileManagerImpl.java
+++ b/source/src/main/java/one/nem/lacerta/source/file/impl/FileManagerImpl.java
@@ -87,7 +87,8 @@ public class FileManagerImpl implements FileManager {
     @Override
     public void saveBitmapAtCurrent(Bitmap bitmap, String fileName) { // TODO-rca: ファイル形式を変更できるようにする？
         try {
-            Files.write(currentDir.resolve(fileName), bitmap.toString().getBytes()); // TODO-rca: エラーハンドリング
+            File file = currentDir.resolve(fileName).toFile();
+            bitmap.compress(Bitmap.CompressFormat.PNG, 100, Files.newOutputStream(file.toPath()));
         } catch (IOException e) {
             e.printStackTrace();
         }