diff --git a/optuna_dashboard/artifact/__init__.py b/optuna_dashboard/artifact/__init__.py
index 06cf2721..d804424b 100644
--- a/optuna_dashboard/artifact/__init__.py
+++ b/optuna_dashboard/artifact/__init__.py
@@ -3,49 +3,39 @@ from __future__ import annotations
 import json
 import mimetypes
 import os.path
-from typing import Any
-from typing import BinaryIO
-from typing import Optional
+from typing import TYPE_CHECKING
 import uuid
 
 from bottle import Bottle
 from bottle import response
 import optuna
-from optuna.storages import BaseStorage
 
 
-try:
-    from typing import Protocol
+if TYPE_CHECKING:
+    from typing import Any
+    from typing import Optional
     from typing import TypedDict
-except ImportError:
-    from typing_extensions import Protocol  # type: ignore
-    from typing_extensions import TypedDict  # type: ignore
+
+    from optuna.storages import BaseStorage
+
+    from .backend import ArtifactBackend
+
+    ArtifactMeta = TypedDict(
+        "ArtifactMeta",
+        {
+            "artifact_id": str,
+            "mimetype": str,
+            "encoding": str,
+            "filename": str,
+        },
+    )
 
 
 ARTIFACTS_ATTR_PREFIX = "dashboard:artifacts:"
 
 
-ArtifactMeta = TypedDict(
-    "ArtifactMeta",
-    {
-        "artifact_id": str,
-        "mimetype": str,
-        "encoding": str,
-        "filename": str,
-    },
-)
-
-
-class ArtifactBackend(Protocol):
-    def open(self, artifact_id: str) -> BinaryIO:
-        ...
-
-    def write(self, artifact_id: str, content_body: BinaryIO) -> None:
-        ...
-
-
 def register_artifact_route(
-    app: Bottle, storage: BaseStorage, artifact_backend: ArtifactBackend
+    app: Bottle, storage: BaseStorage, artifact_backend: Optional[ArtifactBackend]
 ) -> None:
     @app.get("/artifacts/<trial_id:int>/<artifact_id:re:[0-9a-fA-F-]+>")
     def proxy_artifact(trial_id: int, artifact_id: str) -> bytes:
@@ -59,6 +49,15 @@ def register_artifact_route(
             body = f.read()
         return body
 
+    @app.delete("/artifacts/<artifact_id:re:[0-9a-fA-F-]+>")
+    def delete_artifact(artifact_id: str) -> bytes:
+        if artifact_backend is None:
+            response.status = 400  # Bad Request
+            return b"Cannot access to the artifacts."
+        artifact_backend.remove(artifact_id)
+        response.status = 204
+        return b""
+
 
 def upload_artifact(
     backend: ArtifactBackend,
diff --git a/optuna_dashboard/artifact/backend.py b/optuna_dashboard/artifact/backend.py
new file mode 100644
index 00000000..5845b0f9
--- /dev/null
+++ b/optuna_dashboard/artifact/backend.py
@@ -0,0 +1,20 @@
+from __future__ import annotations
+
+from typing import BinaryIO
+
+
+try:
+    from typing import Protocol
+except ImportError:
+    from typing_extensions import Protocol  # type: ignore
+
+
+class ArtifactBackend(Protocol):
+    def open(self, artifact_id: str) -> BinaryIO:
+        ...
+
+    def write(self, artifact_id: str, content_body: BinaryIO) -> None:
+        ...
+
+    def remove(self, artifact_id: str) -> None:
+        ...
diff --git a/optuna_dashboard/artifact/file_system.py b/optuna_dashboard/artifact/file_system.py
index 97d74ef8..e4674b62 100644
--- a/optuna_dashboard/artifact/file_system.py
+++ b/optuna_dashboard/artifact/file_system.py
@@ -4,7 +4,7 @@ import os
 from typing import BinaryIO
 from typing import TYPE_CHECKING
 
-from . import ArtifactBackend
+from .backend import ArtifactBackend
 
 
 class FileSystemBackend:
@@ -20,6 +20,10 @@ class FileSystemBackend:
         with open(filepath, "wb") as f:
             f.write(content_body.read())
 
+    def remove(self, artifact_id: str) -> None:
+        filepath = os.path.join(self._base_path, artifact_id)
+        os.remove(filepath)
+
 
 if TYPE_CHECKING:
     # A mypy-runtime assertion to ensure that LocalArtifactBackend