diff --git a/fastapi/routing.py b/fastapi/routing.py
index 457481e32..6a80080e7 100644
--- a/fastapi/routing.py
+++ b/fastapi/routing.py
@@ -283,7 +283,7 @@ def get_request_handler(
                 raise
             except Exception as e:
                 http_error = HTTPException(
-                    status_code=400, detail="There was an error parsing the body"
+                    status_code=400, detail=f"There was an error parsing the body: {e}"
                 )
                 raise http_error from e
             errors: List[Any] = []