diff --git a/system_tests/clear_datastore.py b/system_tests/clear_datastore.py
index 7ac60f010fc6..8c57022a26fc 100644
--- a/system_tests/clear_datastore.py
+++ b/system_tests/clear_datastore.py
@@ -89,7 +89,7 @@ def remove_kind(kind, client):
 def remove_all_entities(client=None):
     if client is None:
         # Get a client that uses the test dataset.
-        client = datastore.Client(dataset_id=TESTS_DATASET)
+        client = datastore.Client(project=TESTS_DATASET)
     for kind in ALL_KINDS:
         remove_kind(kind, client)
 
diff --git a/system_tests/datastore.py b/system_tests/datastore.py
index 5e8b8083bf75..2869601a52c9 100644
--- a/system_tests/datastore.py
+++ b/system_tests/datastore.py
@@ -46,7 +46,7 @@ def setUpModule():
         client.DATASET = TESTS_DATASET
         Config.CLIENT = datastore.Client()
     else:
-        Config.CLIENT = datastore.Client(dataset_id=EMULATOR_DATASET)
+        Config.CLIENT = datastore.Client(project=EMULATOR_DATASET)
         populate_datastore.add_characters(client=Config.CLIENT)
 
 
diff --git a/system_tests/populate_datastore.py b/system_tests/populate_datastore.py
index b73e6b93e9b2..3c349fdff074 100644
--- a/system_tests/populate_datastore.py
+++ b/system_tests/populate_datastore.py
@@ -91,7 +91,7 @@ def print_func(message):
 def add_characters(client=None):
     if client is None:
         # Get a client that uses the test dataset.
-        client = datastore.Client(dataset_id=TESTS_DATASET)
+        client = datastore.Client(project=TESTS_DATASET)
     with client.transaction() as xact:
         for key_path, character in zip(KEY_PATHS, CHARACTERS):
             if key_path[-1] != character['name']: