diff --git a/include/pybind11/cast.h b/include/pybind11/cast.h
index a9202f6b..8547f283 100644
--- a/include/pybind11/cast.h
+++ b/include/pybind11/cast.h
@@ -500,10 +500,12 @@ public:
     using type_caster<type>::copy_constructor;
 
     bool load(handle src, bool convert) {
-        if (!src || !typeinfo)
+        if (!src || !typeinfo) {
             return false;
-
-        if (PyType_IsSubtype(Py_TYPE(src.ptr()), typeinfo->type)) {
+        } else if (src.ptr() == Py_None) {
+            value = nullptr;
+            return true;
+        } else if (PyType_IsSubtype(Py_TYPE(src.ptr()), typeinfo->type)) {
             auto inst = (instance<type, holder_type> *) src.ptr();
             value = inst->value;
             holder = inst->holder;