diff --git a/app/node_replace_manager.py b/app/node_replace_manager.py
index 03b603c70..d9aab5b22 100644
--- a/app/node_replace_manager.py
+++ b/app/node_replace_manager.py
@@ -46,6 +46,8 @@ class NodeReplaceManager:
         connections: dict[str, list[tuple[str, str, int]]] = {}
         need_replacement: set[str] = set()
         for node_number, node_struct in prompt.items():
+            if "class_type" not in node_struct or "inputs" not in node_struct:
+                continue
             class_type = node_struct["class_type"]
             # need replacement if not in NODE_CLASS_MAPPINGS and has replacement
             if class_type not in nodes.NODE_CLASS_MAPPINGS.keys() and self.has_replacement(class_type):