diff --git a/sdk/monitor/monitor-query/test/internal/unit/modelConverters.unittest.spec.ts b/sdk/monitor/monitor-query/test/internal/unit/modelConverters.unittest.spec.ts
index b64d07286e12..3be80867318a 100644
--- a/sdk/monitor/monitor-query/test/internal/unit/modelConverters.unittest.spec.ts
+++ b/sdk/monitor/monitor-query/test/internal/unit/modelConverters.unittest.spec.ts
@@ -354,8 +354,8 @@ describe("Model unit tests", () => {
 
     it("convertTimespanToInterval", () => {
       const res1 = convertTimespanToInterval({
-        startTime: new Date("2007-11-13T08:00:00"),
-        endTime: new Date("2007-11-16T08:00:00"),
+        startTime: new Date("2007-11-13T08:00:00Z"),
+        endTime: new Date("2007-11-16T08:00:00Z"),
       });
       assert.equal(res1, "2007-11-13T08:00:00.000Z/2007-11-16T08:00:00.000Z");