diff --git a/backend/src/album/dto/create-album.dto.ts b/backend/src/album/dto/create-album.dto.ts
index 83a8d47..95e942b 100644
--- a/backend/src/album/dto/create-album.dto.ts
+++ b/backend/src/album/dto/create-album.dto.ts
@@ -1,5 +1,15 @@
+import { IsNotEmpty, IsString } from 'class-validator';
+
 export class CreateAlbumDto {
+  @IsString()
+  @IsNotEmpty()
   title: string;
+
+  @IsString()
+  @IsNotEmpty()
   artist: string;
+
+  @IsString()
+  @IsNotEmpty()
   genre: string;
 }
diff --git a/backend/src/album/dto/update-album.dto.ts b/backend/src/album/dto/update-album.dto.ts
index ac795d7..8b38f2e 100644
--- a/backend/src/album/dto/update-album.dto.ts
+++ b/backend/src/album/dto/update-album.dto.ts
@@ -1,6 +1,21 @@
+import { IsNotEmpty, IsNumber, IsString } from 'class-validator';
+
 export class UpdateAlbumDto {
+  @IsNumber()
   id: number;
+
+  @IsString()
+  @IsNotEmpty()
   title: string;
+
+  @IsString()
+  @IsNotEmpty()
   artist: string;
+
+  @IsString()
+  @IsNotEmpty()
+
+  @IsString()
+  @IsNotEmpty()
   genre: string;
 }
diff --git a/backend/src/song/dto/create-song.dto.ts b/backend/src/song/dto/create-song.dto.ts
index 93a2357..3481a6c 100644
--- a/backend/src/song/dto/create-song.dto.ts
+++ b/backend/src/song/dto/create-song.dto.ts
@@ -1,6 +1,16 @@
+import { IsNotEmpty, IsNumber, IsString } from 'class-validator';
+
 export class CreateSongDto {
+  @IsString()
+  @IsNotEmpty()
   title: string;
+
+  @IsNumber()
   duration: number;
+
+  @IsNumber()
   trackNumber: number;
+
+  @IsNumber()
   albumId: number;
 }
diff --git a/backend/src/song/dto/update-song.dto.ts b/backend/src/song/dto/update-song.dto.ts
index deaf54d..25d2005 100644
--- a/backend/src/song/dto/update-song.dto.ts
+++ b/backend/src/song/dto/update-song.dto.ts
@@ -1,7 +1,19 @@
+import { IsNotEmpty, IsNumber, IsString } from 'class-validator';
+
 export class UpdateSongDto {
+  @IsNumber()
   id: number;
+
+  @IsString()
+  @IsNotEmpty()
   title: string;
+
+  @IsNumber()
   duration: number;
+
+  @IsNumber()
   trackNumber: number;
+
+  @IsNumber()
   albumId: number;
 }