diff --git a/pylsp/workspace.py b/pylsp/workspace.py
index 290b95ee..c27ec9dc 100644
--- a/pylsp/workspace.py
+++ b/pylsp/workspace.py
@@ -78,7 +78,7 @@ def _rope_project_builder(self, rope_config):
         # TODO: we could keep track of dirty files and validate only those
         if self.__rope is None or self.__rope_config != rope_config:
             rope_folder = rope_config.get("ropeFolder")
-            if "ropeFolder" in rope_config:
+            if rope_folder is not None:
                 self.__rope = Project(self._root_path, ropefolder=rope_folder)
             else:
                 self.__rope = Project(self._root_path)