diff --git a/tests/repository_simulator.py b/tests/repository_simulator.py
index 6377fe0a2b..dc3f0e5721 100644
--- a/tests/repository_simulator.py
+++ b/tests/repository_simulator.py
@@ -397,5 +397,6 @@ def write(self) -> None:
                 f.write(self.fetch_metadata(role))
 
         for role in self.md_delegates:
-            with open(os.path.join(dest_dir, f"{role}.json"), "wb") as f:
+            quoted_role = parse.quote(role, "")
+            with open(os.path.join(dest_dir, f"{quoted_role}.json"), "wb") as f:
                 f.write(self.fetch_metadata(role))