diff --git a/Lib/test/test_import.py b/Lib/test/test_import.py
index c17da10..5582ba8 100644
--- a/Lib/test/test_import.py
+++ b/Lib/test/test_import.py
@@ -397,6 +397,16 @@ class ImportTests(unittest.TestCase):
         finally:
             sys.path.pop(0)
 
+    def test_fromlist_error_messages(self):
+        # Test for issue #21720: fromlist unicode error messages
+        with self.assertRaises(TypeError) as cm:
+            __import__('encodings', fromlist=[u'aliases'])
+        self.assertIn("must be str, not unicode", str(cm.exception))
+
+        with self.assertRaises(TypeError) as cm:
+            __import__('encodings', fromlist=[1])
+        self.assertIn("not a string", str(cm.exception))
+
 
 class PycRewritingTests(unittest.TestCase):
     # Test that the `co_filename` attribute on code objects always points
diff --git a/Python/import.c b/Python/import.c
index 92363b3..263ecf0 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -2567,8 +2567,16 @@ ensure_fromlist(PyObject *mod, PyObject *fromlist, char *buf, Py_ssize_t buflen,
             return 0;
         }
         if (!PyString_Check(item)) {
-            PyErr_SetString(PyExc_TypeError,
-                            "Item in ``from list'' not a string");
+            if (PyUnicode_Check(item)) {
+                PyErr_SetString(
+                    PyExc_TypeError,
+                    "Item in ``from list'' must be str, not unicode");
+            }
+            else {
+                PyErr_SetString(
+                    PyExc_TypeError,
+                    "Item in ``from list'' not a string");
+            }
             Py_DECREF(item);
             return 0;
         }