diff --git a/system/athena/athenad.py b/system/athena/athenad.py
index 78285f018e..55b9476986 100755
--- a/system/athena/athenad.py
+++ b/system/athena/athenad.py
@@ -99,9 +99,9 @@ send_queue: Queue[str] = queue.Queue()
 upload_queue: Queue[UploadItem] = queue.Queue()
 low_priority_send_queue: Queue[str] = queue.Queue()
 log_recv_queue: Queue[str] = queue.Queue()
-cancelled_uploads: set[str] = set()
 
 cur_upload_items: dict[int, UploadItem | None] = {}
+cur_upload_items_lock = threading.Lock()
 
 
 def strip_zst_extension(fn: str) -> str:
@@ -129,8 +129,9 @@ class UploadQueueCache:
   @staticmethod
   def cache(upload_queue: Queue[UploadItem]) -> None:
     try:
-      queue: list[UploadItem | None] = list(upload_queue.queue)
-      items = [asdict(i) for i in queue if i is not None and (i.id not in cancelled_uploads)]
+      with upload_queue.mutex:
+        items = [asdict(item) for item in upload_queue.queue]
+
       Params().put("AthenadUploadQueue", json.dumps(items))
     except Exception:
       cloudlog.exception("athena.UploadQueueCache.cache.exception")
@@ -200,7 +201,8 @@ def retry_upload(tid: int, end_event: threading.Event, increase_count: bool = Tr
     upload_queue.put_nowait(item)
     UploadQueueCache.cache(upload_queue)
 
-    cur_upload_items[tid] = None
+    with cur_upload_items_lock:
+      cur_upload_items[tid] = None
 
     for _ in range(RETRY_DELAY):
       time.sleep(1)
@@ -219,7 +221,8 @@ def cb(sm, item, tid, end_event: threading.Event, sz: int, cur: int) -> None:
   if end_event.is_set():
     raise AbortTransferException
 
-  cur_upload_items[tid] = replace(item, progress=cur / sz if sz else 1)
+  with cur_upload_items_lock:
+    cur_upload_items[tid] = replace(item, progress=cur / sz if sz else 1)
 
 
 def upload_handler(end_event: threading.Event) -> None:
@@ -227,14 +230,10 @@ def upload_handler(end_event: threading.Event) -> None:
   tid = threading.get_ident()
 
   while not end_event.is_set():
-    cur_upload_items[tid] = None
-
     try:
-      cur_upload_items[tid] = item = replace(upload_queue.get(timeout=1), current=True)
-
-      if item.id in cancelled_uploads:
-        cancelled_uploads.remove(item.id)
-        continue
+      with cur_upload_items_lock:
+        cur_upload_items[tid] = None
+        cur_upload_items[tid] = item = replace(upload_queue.get(timeout=1), current=True)
 
       # Remove item if too old
       age = datetime.now() - datetime.fromtimestamp(item.created_at / 1000)
@@ -413,8 +412,13 @@ def uploadFilesToUrls(files_data: list[UploadFileDict]) -> UploadFilesToUrlRespo
 
 @dispatcher.add_method
 def listUploadQueue() -> list[UploadItemDict]:
-  items = list(upload_queue.queue) + list(cur_upload_items.values())
-  return [asdict(i) for i in items if (i is not None) and (i.id not in cancelled_uploads)]
+  with upload_queue.mutex:
+    items = list(upload_queue.queue)
+
+  with cur_upload_items_lock:
+    items += list(cur_upload_items.values())
+
+  return [asdict(item) for item in items]
 
 
 @dispatcher.add_method
@@ -422,13 +426,14 @@ def cancelUpload(upload_id: str | list[str]) -> dict[str, int | str]:
   if not isinstance(upload_id, list):
     upload_id = [upload_id]
 
-  uploading_ids = {item.id for item in list(upload_queue.queue)}
-  cancelled_ids = uploading_ids.intersection(upload_id)
-  if len(cancelled_ids) == 0:
-    return {"success": 0, "error": "not found"}
+  with upload_queue.mutex:
+    remaining_items = [item for item in upload_queue.queue if item.id not in upload_id]
+    if len(remaining_items) == len(upload_queue.queue):
+      return {"success": 0, "error": "not found"}
 
-  cancelled_uploads.update(cancelled_ids)
-  return {"success": 1}
+    upload_queue.queue.clear()
+    upload_queue.queue.extend(remaining_items)
+    return {"success": 1}
 
 @dispatcher.add_method
 def setRouteViewed(route: str) -> dict[str, int | str]:
diff --git a/system/athena/tests/test_athenad.py b/system/athena/tests/test_athenad.py
index a6bfc68930..cee37064b9 100644
--- a/system/athena/tests/test_athenad.py
+++ b/system/athena/tests/test_athenad.py
@@ -78,7 +78,6 @@ class TestAthenadMethods:
 
     athenad.upload_queue = queue.Queue()
     athenad.cur_upload_items.clear()
-    athenad.cancelled_uploads.clear()
 
     for i in os.listdir(Paths.log_root()):
       p = os.path.join(Paths.log_root(), i)
@@ -282,13 +281,10 @@ class TestAthenadMethods:
     athenad.upload_queue.put_nowait(item)
     dispatcher["cancelUpload"](item.id)
 
-    assert item.id in athenad.cancelled_uploads
-
     self._wait_for_upload()
     time.sleep(0.1)
 
     assert athenad.upload_queue.qsize() == 0
-    assert len(athenad.cancelled_uploads) == 0
 
   @with_upload_handler
   def test_cancel_expiry(self):
@@ -331,7 +327,7 @@ class TestAthenadMethods:
     assert items[0] == asdict(item)
     assert not items[0]['current']
 
-    athenad.cancelled_uploads.add(item.id)
+    dispatcher["cancelUpload"](item.id)
     items = dispatcher["listUploadQueue"]()
     assert len(items) == 0
 
@@ -343,7 +339,7 @@ class TestAthenadMethods:
     athenad.upload_queue.put_nowait(item2)
 
     # Ensure canceled items are not persisted
-    athenad.cancelled_uploads.add(item2.id)
+    dispatcher["cancelUpload"](item2.id)
 
     # serialize item
     athenad.UploadQueueCache.cache(athenad.upload_queue)