diff --git a/changelog/pending/20221102--sdk-python--handle-none-being-passed-to-register_resource_outputs.yaml b/changelog/pending/20221102--sdk-python--handle-none-being-passed-to-register_resource_outputs.yaml
new file mode 100644
index 000000000000..08c8d2111bb8
--- /dev/null
+++ b/changelog/pending/20221102--sdk-python--handle-none-being-passed-to-register_resource_outputs.yaml
@@ -0,0 +1,4 @@
+changes:
+- type: fix
+  scope: sdk/python
+  description: Handle None being passed to register_resource_outputs.
diff --git a/sdk/python/lib/pulumi/runtime/resource.py b/sdk/python/lib/pulumi/runtime/resource.py
index 6941325f1468..a9a310e0e966 100644
--- a/sdk/python/lib/pulumi/runtime/resource.py
+++ b/sdk/python/lib/pulumi/runtime/resource.py
@@ -682,7 +682,9 @@ def register_resource_outputs(
 ):
     async def do_register_resource_outputs():
         urn = await res.urn.future()
-        serialized_props = await rpc.serialize_properties(outputs, {})
+        # serialize_properties expects a collection (empty is fine) but not None, but this is called pretty
+        # much directly by users who could pass None in (although the type hints say they shouldn't).
+        serialized_props = await rpc.serialize_properties(outputs or {}, {})
         log.debug(
             f"register resource outputs prepared: urn={urn}, props={serialized_props}"
         )