diff --git a/scripts/py_matter_idl/matter_idl/generators/bridge/__init__.py b/scripts/py_matter_idl/matter_idl/generators/bridge/__init__.py
index f48c5eac5cc080..5325ce8043f10e 100644
--- a/scripts/py_matter_idl/matter_idl/generators/bridge/__init__.py
+++ b/scripts/py_matter_idl/matter_idl/generators/bridge/__init__.py
@@ -88,7 +88,7 @@ def get_field_type(definition: Field, cluster: Cluster, idl: Idl):
         cType = 'std::vector<{}>'.format(cType)
     if definition.is_nullable:
         cType = '::chip::app::DataModel::Nullable<{}>'.format(cType)
-    if definition.is_nullable:
+    if definition.is_optional:
         cType = '::chip::Optional<{}>'.format(cType)
     return cType