diff --git a/panda/src/event/pythonTask.cxx b/panda/src/event/pythonTask.cxx
index 6ea95be752..02e9185090 100644
--- a/panda/src/event/pythonTask.cxx
+++ b/panda/src/event/pythonTask.cxx
@@ -97,9 +97,17 @@ PythonTask::
     _exc_traceback = nullptr;
   }
 
+  PyObject *self = __self__;
+  if (self != nullptr) {
+    PyObject_GC_UnTrack(self);
+    __self__ = nullptr;
+    Py_DECREF(self);
+  }
+
+  // All of these may have already been cleared by __clear__.
   Py_XDECREF(_function);
-  Py_DECREF(_args);
-  Py_DECREF(__dict__);
+  Py_XDECREF(_args);
+  Py_XDECREF(__dict__);
   Py_XDECREF(_exception);
   Py_XDECREF(_exc_value);
   Py_XDECREF(_exc_traceback);
@@ -364,14 +372,13 @@ __getattribute__(PyObject *self, PyObject *attr) const {
  */
 int PythonTask::
 __traverse__(visitproc visit, void *arg) {
-/*
+  Py_VISIT(__self__);
   Py_VISIT(_function);
   Py_VISIT(_args);
   Py_VISIT(_upon_death);
   Py_VISIT(_owner);
   Py_VISIT(__dict__);
   Py_VISIT(_generator);
-*/
   return 0;
 }
 
@@ -380,17 +387,58 @@ __traverse__(visitproc visit, void *arg) {
  */
 int PythonTask::
 __clear__() {
-/*
   Py_CLEAR(_function);
   Py_CLEAR(_args);
   Py_CLEAR(_upon_death);
   Py_CLEAR(_owner);
   Py_CLEAR(__dict__);
   Py_CLEAR(_generator);
-*/
+
+  Py_CLEAR(__self__);
   return 0;
 }
 
+/**
+ *
+ */
+bool PythonTask::
+unref() const {
+  if (!AsyncTask::unref()) {
+    // It was cleaned up by the Python garbage collector.
+    return false;
+  }
+
+  // If the last reference to the object is the one being held by Python,
+  // check whether the Python wrapper itself is also at a refcount of 1.
+  bool result = true;
+  if (get_ref_count() == 1) {
+    PyGILState_STATE gstate = PyGILState_Ensure();
+
+    // Check whether we have a Python wrapper.  This is not the case if the
+    // object has been created by C++ and never been exposed to Python code.
+    PyObject *self = __self__;
+    if (self != nullptr) {
+      int ref_count = Py_REFCNT(self);
+      assert(ref_count > 0);
+      if (ref_count == 1) {
+        // The last reference to the Python wrapper is being held by us.
+        // Break the reference cycle and allow the object to go away.
+        if (!AsyncTask::unref()) {
+          PyObject_GC_UnTrack(self);
+          ((Dtool_PyInstDef *)self)->_memory_rules = false;
+          __self__ = nullptr;
+          Py_DECREF(self);
+
+          // Let the caller destroy the object.
+          result = false;
+        }
+      }
+    }
+    PyGILState_Release(gstate);
+  }
+  return result;
+}
+
 /**
  * Cancels this task.  This is equivalent to remove(), except for coroutines,
  * for which it will throw an exception into any currently pending await.
diff --git a/panda/src/event/pythonTask.h b/panda/src/event/pythonTask.h
index 88bee56bd9..148252e999 100644
--- a/panda/src/event/pythonTask.h
+++ b/panda/src/event/pythonTask.h
@@ -89,6 +89,14 @@ PUBLISHED:
   // custom variables may be stored.
   PyObject *__dict__;
 
+public:
+  // This holds a reference to the Python wrapper corresponding to this
+  // PythonTask object.  It is necessary for this to remain consistent for
+  // the __traverse__ method to work correctly.
+  mutable PyObject *__self__ = nullptr;
+
+  virtual bool unref() const;
+
 protected:
   virtual bool cancel();
 
diff --git a/tests/event/test_pythontask.py b/tests/event/test_pythontask.py
index d6806b4f72..584788494f 100644
--- a/tests/event/test_pythontask.py
+++ b/tests/event/test_pythontask.py
@@ -1,7 +1,26 @@
 from panda3d.core import PythonTask
+from contextlib import contextmanager
 import pytest
 import types
 import sys
+import gc
+
+
+@contextmanager
+def gc_disabled():
+    gc.disable()
+    gc.collect()
+    gc.freeze()
+    gc.set_debug(gc.DEBUG_SAVEALL)
+
+    try:
+        yield
+    finally:
+        gc.set_debug(0)
+        gc.garbage.clear()
+        gc.unfreeze()
+        gc.collect()
+        gc.enable()
 
 
 def test_pythontask_property_builtin():
@@ -76,3 +95,23 @@ def test_pythontask_dict_set():
     rc2 = sys.getrefcount(d)
 
     assert rc1 == rc2
+
+
+def test_pythontask_cycle():
+    with gc_disabled():
+        task = PythonTask()
+        assert gc.is_tracked(task)
+        task.marker = 'test_pythontask_cycle'
+        task.prop = task
+
+        del task
+
+        gc.collect()
+        assert len(gc.garbage) > 0
+
+        for g in gc.garbage:
+            if isinstance(g, PythonTask) and \
+               getattr(g, 'marker', None) == 'test_pythontask_cycle':
+                break
+        else:
+            pytest.fail('not found in garbage')