diff --git a/src/Mod/MeshPart/App/Mesher.h b/src/Mod/MeshPart/App/Mesher.h
index 3839273e4..7ab6b89bd 100644
--- a/src/Mod/MeshPart/App/Mesher.h
+++ b/src/Mod/MeshPart/App/Mesher.h
@@ -24,6 +24,7 @@
 #define MESHPART_MESHER_H
 
 #include <sstream>
+#include <Base/Stream.h>
 
 class TopoDS_Shape;