diff --git a/types/prosemirror-model/index.d.ts b/types/prosemirror-model/index.d.ts
index aa02f9b770..a86037d0f8 100644
--- a/types/prosemirror-model/index.d.ts
+++ b/types/prosemirror-model/index.d.ts
@@ -1323,7 +1323,7 @@ export class Schema<N extends string = any, M extends string = any> {
   /**
    * A map from mark names to mark type objects.
    */
-  marks: { [name in M]: MarkType<Schema<N, M>> } & { [key: string]: NodeType<Schema<N, M>> };
+  marks: { [name in M]: MarkType<Schema<N, M>> } & { [key: string]: MarkType<Schema<N, M>> };
   /**
    * The type of the [default top node](#model.SchemaSpec.topNode)
    * for this schema.