diff --git a/.changeset/thick-donkeys-fold.md b/.changeset/thick-donkeys-fold.md
new file mode 100644
index 0000000000..f341724188
--- /dev/null
+++ b/.changeset/thick-donkeys-fold.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-catalog': patch
+---
+
+Fix for Diagram component using hard coded namespace.
diff --git a/plugins/catalog/src/components/SystemDiagramCard/SystemDiagramCard.tsx b/plugins/catalog/src/components/SystemDiagramCard/SystemDiagramCard.tsx
index 5fd32a6298..36fac17d0a 100644
--- a/plugins/catalog/src/components/SystemDiagramCard/SystemDiagramCard.tsx
+++ b/plugins/catalog/src/components/SystemDiagramCard/SystemDiagramCard.tsx
@@ -157,7 +157,9 @@ export function SystemDiagramCard() {
         kind: ['Component', 'API', 'Resource', 'System', 'Domain'],
         'spec.system': [
           currentSystemName,
-          `${ENTITY_DEFAULT_NAMESPACE}/${currentSystemName}`,
+          `${
+            entity.metadata.namespace || ENTITY_DEFAULT_NAMESPACE
+          }/${currentSystemName}`,
         ],
       },
     });