diff --git a/deepdiff/helper.py b/deepdiff/helper.py
index 3fc61183..45379caa 100644
--- a/deepdiff/helper.py
+++ b/deepdiff/helper.py
@@ -690,7 +690,7 @@ def datetime_normalize(
         datetime.timezone, "BaseTzInfo"
     ] = datetime.timezone.utc,
 ) -> Any:
-    if truncate_datetime:
+    if truncate_datetime and isinstance(obj, (datetime.datetime, datetime.time)):
         if truncate_datetime == 'second':
             obj = obj.replace(microsecond=0)
         elif truncate_datetime == 'minute':
diff --git a/tests/test_diff_datetime.py b/tests/test_diff_datetime.py
index c3905291..1b48642a 100644
--- a/tests/test_diff_datetime.py
+++ b/tests/test_diff_datetime.py
@@ -1,5 +1,5 @@
 import pytz
-from datetime import date, datetime, time, timezone
+from datetime import date, datetime, time, timedelta, timezone
 from deepdiff import DeepDiff
 
 
@@ -123,3 +123,17 @@ def test_datetime_within_array_with_timezone_diff(self):
         assert not DeepDiff(d1, d2)
         assert not DeepDiff(d1, d2, ignore_order=True)
         assert not DeepDiff(d1, d2, truncate_datetime='second')
+
+    def test_truncate_datetime_with_date_and_timedelta(self):
+        """truncate_datetime must not be applied to types that cannot be truncated."""
+        for truncate_datetime in ('second', 'minute', 'hour', 'day'):
+            d1 = {"a": date(2020, 5, 17)}
+            d2 = {"a": date(2020, 5, 17)}
+            assert not DeepDiff(d1, d2, truncate_datetime=truncate_datetime)
+
+            d2 = {"a": date(2020, 5, 18)}
+            assert DeepDiff(d1, d2, truncate_datetime=truncate_datetime)
+
+            d1 = {"a": timedelta(days=1)}
+            d2 = {"a": timedelta(days=2)}
+            assert DeepDiff(d1, d2, truncate_datetime=truncate_datetime)