diff --git a/src/client/testing/testController/common/resultResolver.ts b/src/client/testing/testController/common/resultResolver.ts
index fd927262348d..aa9f2a541f51 100644
--- a/src/client/testing/testController/common/resultResolver.ts
+++ b/src/client/testing/testController/common/resultResolver.ts
@@ -216,9 +216,11 @@ export class PythonResultResolver implements ITestResultResolver {
                         throw new Error('Parent test item not found');
                     }
                 } else if (rawTestExecData.result[keyTemp].outcome === 'subtest-success') {
-                    // split on " " since the subtest ID has the parent test ID in the first part of the ID.
-                    const parentTestCaseId = keyTemp.split(' [')[0];
-                    const subtestId = `[${keyTemp.split(' [')[1]}`;
+                    // split only on first " [" since the subtest ID has the parent test ID in the first part of the ID.
+                    const index = keyTemp.indexOf(' [');
+                    const parentTestCaseId = keyTemp.substring(0, index);
+                    // add one to index to remove the space from the start of the subtest ID
+                    const subtestId = keyTemp.substring(index + 1, keyTemp.length);
                     const parentTestItem = this.runIdToTestItem.get(parentTestCaseId);
 
                     // find the subtest's parent test item
diff --git a/src/test/testing/testController/resultResolver.unit.test.ts b/src/test/testing/testController/resultResolver.unit.test.ts
index eff985c7e5e8..694fdacb8049 100644
--- a/src/test/testing/testController/resultResolver.unit.test.ts
+++ b/src/test/testing/testController/resultResolver.unit.test.ts
@@ -270,15 +270,16 @@ suite('Result Resolver tests', () => {
                 testProvider,
                 workspaceUri,
             );
-            const mockSubtestItem = createMockTestItem('parentTest [subTest with spaces]');
+            const subtestName = 'parentTest [subTest with spaces and [brackets]]';
+            const mockSubtestItem = createMockTestItem(subtestName);
             // add a mock test item to the map of known VSCode ids to run ids
             resultResolver.runIdToVSid.set('mockTestItem2', 'mockTestItem2');
             // creates a mock test item with a space which will be used to split the runId
-            resultResolver.runIdToVSid.set('parentTest [subTest with spaces]', 'parentTest [subTest with spaces]');
+            resultResolver.runIdToVSid.set(subtestName, subtestName);
 
             // add this mock test to the map of known test items
             resultResolver.runIdToTestItem.set('parentTest', mockTestItem2);
-            resultResolver.runIdToTestItem.set('parentTest [subTest with spaces]', mockSubtestItem);
+            resultResolver.runIdToTestItem.set(subtestName, mockSubtestItem);
 
             let generatedId: string | undefined;
             testControllerMock
@@ -294,12 +295,12 @@ suite('Result Resolver tests', () => {
                 cwd: workspaceUri.fsPath,
                 status: 'success',
                 result: {
-                    'parentTest [subTest with spaces]': {
+                    'parentTest [subTest with spaces and [brackets]]': {
                         test: 'parentTest',
                         outcome: 'subtest-success', // failure, passed-unexpected, skipped, success, expected-failure, subtest-failure, subtest-succcess
                         message: 'message',
                         traceback: 'traceback',
-                        subtest: 'parentTest [subTest with spaces]',
+                        subtest: subtestName,
                     },
                 },
                 error: '',
@@ -310,7 +311,7 @@ suite('Result Resolver tests', () => {
 
             // verify that the passed function was called for the single test item
             assert.ok(generatedId);
-            assert.strictEqual(generatedId, '[subTest with spaces]');
+            assert.strictEqual(generatedId, '[subTest with spaces and [brackets]]');
         });
         test('resolveExecution handles failed tests correctly', async () => {
             // test specific constants used expected values