diff --git a/superset/db_engine_specs/athena.py b/superset/db_engine_specs/athena.py
index 2394fe088da65..9e1d798a7cb03 100644
--- a/superset/db_engine_specs/athena.py
+++ b/superset/db_engine_specs/athena.py
@@ -69,7 +69,7 @@ def convert_dttm(
         if tt == utils.TemporalType.DATE:
             return f"DATE '{dttm.date().isoformat()}'"
         if tt == utils.TemporalType.TIMESTAMP:
-            datetime_formatted = dttm.isoformat(timespec="microseconds")
+            datetime_formatted = dttm.isoformat(sep=" ", timespec="milliseconds")
             return f"""TIMESTAMP '{datetime_formatted}'"""
         return None
 
diff --git a/tests/unit_tests/db_engine_specs/test_athena.py b/tests/unit_tests/db_engine_specs/test_athena.py
index a35d8eddfb0ad..d7c1a3f606fca 100644
--- a/tests/unit_tests/db_engine_specs/test_athena.py
+++ b/tests/unit_tests/db_engine_specs/test_athena.py
@@ -39,7 +39,7 @@ def test_convert_dttm(app_context: AppContext, dttm: datetime) -> None:
 
     assert (
         AthenaEngineSpec.convert_dttm("TIMESTAMP", dttm)
-        == "TIMESTAMP '2019-01-02T03:04:05.678900'"
+        == "TIMESTAMP '2019-01-02 03:04:05.678'"
     )