diff --git a/src/SMESH/SMESH_Mesh.hxx b/src/SMESH/SMESH_Mesh.hxx
index 2b926f5dd..8e01301b6 100644
--- a/src/SMESH/SMESH_Mesh.hxx
+++ b/src/SMESH/SMESH_Mesh.hxx
@@ -344,7 +344,6 @@ private:
 protected:
   int                        _id;           // id given by creator (unique within the creator instance)
   int                        _studyId;
-  int                        _idDoc;        // id given by SMESHDS_Document
   int                        _groupId;      // id generator for group objects
   int                        _nbSubShapes;  // initial nb of subshapes in the shape to mesh
   bool                       _isShapeToMesh;// set to true when a shape is given (only once)