because you didn't add QVTKWidget's lib , they are -lQVTK -lvtkQtChart -- View this message in context: http://vtk.1045678.n5.nabble.com/undefined-reference-to-QVTKWidget-QVTKWidget-tp1245232p4586720.html Sent from the VTK - Users mailing list archive at Nabble.com.