diff -r 104fdc42bcd1 Lib/test/test_coroutines.py
--- a/Lib/test/test_coroutines.py	Tue Dec 06 13:43:46 2016 +0200
+++ b/Lib/test/test_coroutines.py	Tue Dec 06 20:38:53 2016 -0800
@@ -1552,6 +1552,46 @@
                 warnings.simplefilter("error")
                 run_async(foo())
 
+    def test_for_11(self):
+        class F:
+            def __aiter__(self):
+                return self
+            def __anext__(self):
+                return self
+            def __await__(self):
+                1 / 0
+
+        async def main():
+            async for _ in F():
+                pass
+
+        with self.assertRaisesRegex(TypeError,
+                                    'an invalid object from __anext__') as c:
+            main().send(None)
+
+        err = c.exception
+        self.assertIsNone(err.__cause__)
+        self.assertIsInstance(err.__context__, ZeroDivisionError)
+
+    def test_for_12(self):
+        class F:
+            def __aiter__(self):
+                return self
+            def __await__(self):
+                1 / 0
+
+        async def main():
+            async for _ in F():
+                pass
+
+        with self.assertRaisesRegex(TypeError,
+                                    'an invalid object from __aiter__') as c:
+            main().send(None)
+
+        err = c.exception
+        self.assertIsNone(err.__cause__)
+        self.assertIsInstance(err.__context__, ZeroDivisionError)
+
     def test_for_tuple(self):
         class Done(Exception): pass
 
diff -r 104fdc42bcd1 Python/ceval.c
--- a/Python/ceval.c	Tue Dec 06 13:43:46 2016 +0200
+++ b/Python/ceval.c	Tue Dec 06 20:38:53 2016 -0800
@@ -1979,13 +1979,16 @@
 
             awaitable = _PyCoro_GetAwaitableIter(iter);
             if (awaitable == NULL) {
-                SET_TOP(NULL);
+                PyObject *exc, *val, *tb;
+                PyErr_Fetch(&exc, &val, &tb);
                 PyErr_Format(
                     PyExc_TypeError,
                     "'async for' received an invalid object "
                     "from __aiter__: %.100s",
                     Py_TYPE(iter)->tp_name);
-
+                _PyErr_ChainExceptions(exc, val, tb);
+
+                SET_TOP(NULL);
                 Py_DECREF(iter);
                 goto error;
             } else {
@@ -2036,11 +2039,14 @@
 
             awaitable = _PyCoro_GetAwaitableIter(next_iter);
             if (awaitable == NULL) {
+                PyObject *exc, *val, *tb;
+                PyErr_Fetch(&exc, &val, &tb);
                 PyErr_Format(
                     PyExc_TypeError,
                     "'async for' received an invalid object "
                     "from __anext__: %.100s",
                     Py_TYPE(next_iter)->tp_name);
+                _PyErr_ChainExceptions(exc, val, tb);
 
                 Py_DECREF(next_iter);
                 goto error;