diff --git a/qucs/diagrams/marker.h b/qucs/diagrams/marker.h
index eed3ff02e..1da991c21 100644
--- a/qucs/diagrams/marker.h
+++ b/qucs/diagrams/marker.h
@@ -18,6 +18,8 @@
 #ifndef MARKER_H
 #define MARKER_H
 
+#include <vector>
+
 #include "element.h"
 #include "viewpainter.h"