diff --git a/bigquery/google/cloud/bigquery/table.py b/bigquery/google/cloud/bigquery/table.py
index c145d6a9dc1c..cb72dde189b2 100644
--- a/bigquery/google/cloud/bigquery/table.py
+++ b/bigquery/google/cloud/bigquery/table.py
@@ -1335,7 +1335,10 @@ def expiration_ms(self):
 
     @expiration_ms.setter
     def expiration_ms(self, value):
-        self._properties["expirationMs"] = str(value)
+        if value is not None:
+            # Allow explicitly setting the expiration to None.
+            value = str(value)
+        self._properties["expirationMs"] = value
 
     @property
     def require_partition_filter(self):
diff --git a/bigquery/tests/unit/test_table.py b/bigquery/tests/unit/test_table.py
index 04a67c603ba9..d84fa6e4b1c8 100644
--- a/bigquery/tests/unit/test_table.py
+++ b/bigquery/tests/unit/test_table.py
@@ -1683,3 +1683,8 @@ def test___repr___explicit(self):
             "type=DAY)"
         )
         self.assertEqual(repr(time_partitioning), expected)
+
+    def test_set_expiration_w_none(self):
+        time_partitioning = self._make_one()
+        time_partitioning.expiration_ms = None
+        assert time_partitioning._properties["expirationMs"] is None