diff --git a/tartiflette_asgi/endpoints.py b/tartiflette_asgi/endpoints.py
index 93f46b4..7966b4a 100644
--- a/tartiflette_asgi/endpoints.py
+++ b/tartiflette_asgi/endpoints.py
@@ -1,4 +1,6 @@
 import typing
+import json
+
 
 from starlette.background import BackgroundTasks
 from starlette.datastructures import QueryParams
@@ -37,7 +39,10 @@ async def post(self, request: Request) -> Response:
         content_type = request.headers.get("Content-Type", "")
 
         if "application/json" in content_type:
-            data = await request.json()
+            try:
+                data = await request.json()
+            except json.JSONDecodeError:
+                return JSONResponse({"error": "Invalid JSON."}, 400)
         elif "application/graphql" in content_type:
             body = await request.body()
             data = {"query": body.decode()}
diff --git a/tests/test_graphql_api.py b/tests/test_graphql_api.py
index a85b413..5cb46a7 100644
--- a/tests/test_graphql_api.py
+++ b/tests/test_graphql_api.py
@@ -27,6 +27,14 @@ def test_post_json(client: TestClient):
     assert response.json() == {"data": {"hello": "Hello stranger"}}
 
 
+def test_post_invalid_json(client: TestClient):
+    response = client.post(
+        "/", data="{test", headers={"content-type": "application/json"}
+    )
+    assert response.status_code == 400
+    assert response.json() == {"error": "Invalid JSON."}
+
+
 def test_post_graphql(client: TestClient):
     response = client.post(
         "/", data="{ hello }", headers={"content-type": "application/graphql"}