diff --git a/google/cloud/bigquery/job/base.py b/google/cloud/bigquery/job/base.py
index 6f9726181..550ba6b91 100644
--- a/google/cloud/bigquery/job/base.py
+++ b/google/cloud/bigquery/job/base.py
@@ -218,8 +218,11 @@ def job_timeout_ms(self, value):
                 err.__traceback__
             )
 
-        """ Docs indicate a string is expected by the API """
-        self._properties["jobTimeoutMs"] = str(value)
+        if value is not None:
+            # docs indicate a string is expected by the API
+            self._properties["jobTimeoutMs"] = str(value)
+        else:
+            self._properties.pop("jobTimeoutMs", None)
 
     @property
     def labels(self):
diff --git a/tests/unit/job/test_base.py b/tests/unit/job/test_base.py
index a7337afd2..0e9786b3e 100644
--- a/tests/unit/job/test_base.py
+++ b/tests/unit/job/test_base.py
@@ -1320,3 +1320,21 @@ def test_job_timeout_ms(self):
         # Confirm that integers get converted to strings.
         job_config.job_timeout_ms = 5000
         assert job_config.job_timeout_ms == "5000"  # int is converted to string
+
+    def test_job_timeout_is_none_when_set_none(self):
+        job_config = self._make_one()
+        job_config.job_timeout_ms = None
+        # Confirm value is None and not literal string 'None'
+        assert job_config.job_timeout_ms is None
+
+    def test_job_timeout_properties(self):
+        # Make sure any value stored in properties is erased 
+        # when setting job_timeout to None.
+        job_config = self._make_one()
+        job_config.job_timeout_ms = 4200
+        assert job_config.job_timeout_ms == "4200"
+        assert job_config._properties.get("jobTimeoutMs") == "4200"
+
+        job_config.job_timeout_ms = None
+        assert job_config.job_timeout_ms is None
+        assert "jobTimeoutMs" not in job_config._properties