diff --git a/google/auth/aws.py b/google/auth/aws.py
index 28c065d3c..4ea1b38b8 100644
--- a/google/auth/aws.py
+++ b/google/auth/aws.py
@@ -531,7 +531,7 @@ def _get_metadata_security_credentials(
             google.auth.exceptions.RefreshError: If an error occurs while
                 retrieving the AWS security credentials.
         """
-        headers = {"Content-Type": "application/json"}
+        headers = {}
         if imdsv2_session_token is not None:
             headers["X-aws-ec2-metadata-token"] = imdsv2_session_token