diff --git a/google/auth/_default.py b/google/auth/_default.py
index 63009dfb8..d58d0c3aa 100644
--- a/google/auth/_default.py
+++ b/google/auth/_default.py
@@ -30,6 +30,7 @@
 _LOGGER = logging.getLogger(__name__)
 
 # Valid types accepted for file-based credentials.
+_ANONYMOUS_TYPE = "anonymous"
 _AUTHORIZED_USER_TYPE = "authorized_user"
 _SERVICE_ACCOUNT_TYPE = "service_account"
 _EXTERNAL_ACCOUNT_TYPE = "external_account"
@@ -37,6 +38,7 @@
 _IMPERSONATED_SERVICE_ACCOUNT_TYPE = "impersonated_service_account"
 _GDCH_SERVICE_ACCOUNT_TYPE = "gdch_service_account"
 _VALID_TYPES = (
+    _ANONYMOUS_TYPE,
     _AUTHORIZED_USER_TYPE,
     _SERVICE_ACCOUNT_TYPE,
     _EXTERNAL_ACCOUNT_TYPE,
@@ -209,6 +211,8 @@ def _load_credentials_from_info(
         )
     elif credential_type == _GDCH_SERVICE_ACCOUNT_TYPE:
         credentials, project_id = _get_gdch_service_account_credentials(filename, info)
+    elif credential_type == _ANONYMOUS_TYPE:
+        credentials, project_id = _get_anonymous_credentials()
     else:
         raise exceptions.DefaultCredentialsError(
             "The file {file} does not have a valid type. "
@@ -428,6 +432,14 @@ def _get_external_account_authorized_user_credentials(
     return credentials, None
 
 
+def _get_anonymous_credentials():
+    from google.auth import credentials
+
+    credentials = credentials.AnonymousCredentials()
+
+    return credentials, None
+
+
 def _get_authorized_user_credentials(filename, info, scopes=None):
     from google.oauth2 import credentials
 
diff --git a/tests/data/anonymous.json b/tests/data/anonymous.json
new file mode 100644
index 000000000..6db7887c3
--- /dev/null
+++ b/tests/data/anonymous.json
@@ -0,0 +1 @@
+{"type": "anonymous"}
diff --git a/tests/test__default.py b/tests/test__default.py
index cb9a7c130..ce4201317 100644
--- a/tests/test__default.py
+++ b/tests/test__default.py
@@ -140,6 +140,7 @@
     "service_account_impersonation_url": SERVICE_ACCOUNT_IMPERSONATION_URL,
     "workforce_pool_user_project": WORKFORCE_POOL_USER_PROJECT,
 }
+ANONYMOUS_DATA = {"type": "anonymous"}
 
 IMPERSONATED_SERVICE_ACCOUNT_AUTHORIZED_USER_SOURCE_FILE = os.path.join(
     DATA_DIR, "impersonated_service_account_authorized_user_source.json"
@@ -160,6 +161,7 @@
 EXTERNAL_ACCOUNT_AUTHORIZED_USER_NON_GDU_FILE = os.path.join(
     DATA_DIR, "external_account_authorized_user_non_gdu.json"
 )
+ANONYMOUS_FILE = os.path.join(DATA_DIR, "anonymous.json")
 
 MOCK_CREDENTIALS = mock.Mock(spec=credentials.CredentialsWithQuotaProject)
 MOCK_CREDENTIALS.with_quota_project.return_value = MOCK_CREDENTIALS
@@ -1362,3 +1364,15 @@ def test_quota_gce_credentials(unused_get, unused_ping):
         quota_project_id=explicit_quota
     )
     assert credentials.quota_project_id == explicit_quota
+
+
+def test_load_credentials_from_file_anonymous():
+    credentials, project_id = _default.load_credentials_from_file(ANONYMOUS_FILE)
+    assert isinstance(credentials, google.auth.credentials.Credentials)
+    assert project_id is None
+
+
+def test_load_credentials_from_dict_anonymous():
+    credentials, project_id = _default.load_credentials_from_dict(ANONYMOUS_DATA)
+    assert isinstance(credentials, google.auth.credentials.Credentials)
+    assert project_id is None