diff --git a/lib/iris/tests/unit/common/metadata/test_BaseMetadata.py b/lib/iris/tests/unit/common/metadata/test_BaseMetadata.py
index 4ff8ec0de6..7cb8e3394b 100644
--- a/lib/iris/tests/unit/common/metadata/test_BaseMetadata.py
+++ b/lib/iris/tests/unit/common/metadata/test_BaseMetadata.py
@@ -53,6 +53,19 @@ def test_repr(self):
         )
         self.assertEqual(expected, repr(metadata))
 
+    def test_str(self):
+        metadata = self.cls(
+            standard_name="",
+            long_name=None,
+            var_name=self.var_name,
+            units=self.units,
+            attributes={},
+        )
+        expected = (
+            f"BaseMetadata(var_name={self.var_name!r}, units={self.units!r})"
+        )
+        self.assertEqual(expected, str(metadata))
+
     def test__fields(self):
         expected = (
             "standard_name",