diff --git a/src/internal/operators/debounceTime.ts b/src/internal/operators/debounceTime.ts
index 78cd632c63e..79345ebb7f6 100644
--- a/src/internal/operators/debounceTime.ts
+++ b/src/internal/operators/debounceTime.ts
@@ -114,6 +114,8 @@ export function debounceTime<T>(dueTime: number, scheduler: SchedulerLike = asyn
         undefined,
         () => {
           // Teardown.
+          // unschedule dangling task, if any, if we unsubscribe before complete
+          activeTask?.unsubscribe();
           lastValue = activeTask = null;
         }
       )