diff --git a/cirq-core/cirq/experiments/xeb_simulation_test.py b/cirq-core/cirq/experiments/xeb_simulation_test.py
index 185fa070366..feecab4a3ef 100644
--- a/cirq-core/cirq/experiments/xeb_simulation_test.py
+++ b/cirq-core/cirq/experiments/xeb_simulation_test.py
@@ -59,7 +59,7 @@ def test_simulate_circuit_length_validation():
         )
         for _ in range(2)
     ]
-    cycle_depths = np.arange(3, 50, 9)
+    cycle_depths = np.arange(3, 50, 9, dtype=np.int64)
     with pytest.raises(ValueError, match='.*not long enough.*'):
         _ = simulate_2q_xeb_circuits(circuits=circuits, cycle_depths=cycle_depths)
 
@@ -127,7 +127,7 @@ def test_incremental_simulate(multiprocess):
         )
         for _ in range(20)
     ]
-    cycle_depths = np.arange(3, 100, 9)
+    cycle_depths = np.arange(3, 100, 9, dtype=np.int64)
 
     if multiprocess:
         pool = multiprocessing.Pool()