diff --git a/docker-compose.example.yml b/docker-compose.example.yml
index e4aa43c..1985269 100644
--- a/docker-compose.example.yml
+++ b/docker-compose.example.yml
@@ -92,6 +92,7 @@ services:
     environment:
       - MINIO_ROOT_USER=minioadmin
       - MINIO_ROOT_PASSWORD=minioadmin
+      - MINIO_REGION=auto
     ports:
       - "29001:9000"    # S3 API
       - "29000:29000"   # Web Console
diff --git a/scripts/generate_docker_compose.py b/scripts/generate_docker_compose.py
index aa0b820..69ad292 100644
--- a/scripts/generate_docker_compose.py
+++ b/scripts/generate_docker_compose.py
@@ -95,6 +95,7 @@ def generate_minio_service(config: dict) -> str:
     environment:
       - MINIO_ROOT_USER={config['s3_access_key']}
       - MINIO_ROOT_PASSWORD={config['s3_secret_key']}
+      - MINIO_REGION=auto
     ports:
       - "29001:9000"    # S3 API
       - "29000:29000"   # Web Console
diff --git a/src/kohakuhub/config.py b/src/kohakuhub/config.py
index eff3329..698988e 100644
--- a/src/kohakuhub/config.py
+++ b/src/kohakuhub/config.py
@@ -16,7 +16,7 @@ class S3Config(BaseModel):
     access_key: str = "test-access-key"
     secret_key: str = "test-secret-key"
     bucket: str = "test-bucket"
-    region: str = "auto"  # auto (recommended), us-east-1, or specific AWS region
+    region: str = "us-east-1"  # auto (recommended), us-east-1, or specific AWS region
     force_path_style: bool = True
     signature_version: str | None = None  # s3v4 (R2, AWS S3) or None/s3v2 (MinIO)
 
@@ -195,7 +195,7 @@ def load_config(path: str = None) -> Config:
             access_key=os.environ.get("KOHAKU_HUB_S3_ACCESS_KEY", "test-access-key"),
             secret_key=os.environ.get("KOHAKU_HUB_S3_SECRET_KEY", "test-secret-key"),
             bucket=os.environ.get("KOHAKU_HUB_S3_BUCKET", "test-bucket"),
-            region=os.environ.get("KOHAKU_HUB_S3_REGION", "auto"),
+            region=os.environ.get("KOHAKU_HUB_S3_REGION", "us-east-1"),
             signature_version=os.environ.get("KOHAKU_HUB_S3_SIGNATURE_VERSION", None),
         )