We investigated with molecular dynamics simulation the mechanical responses of VN (0 0 1) thin films subjected to indentation with a diamond columnar indenter. We calculated the generalized stacking-fault energies as a function of the displacement in the 1 1 0 directions on the {0 0 1}, {1 1 0}, and {1 1 1} planes, and analyzed systematically the microstructures and their evolution during the indentation with the centro-symmetry parameters and the slices of the VN films. We found the slips on {1 1 0}1 1 0 of the VN film under indentation at the initial stage. With the increase of indentation depth, slips are also activated on {1 1 1}1 1 0 and {1 0 0}0 1 1 systems. We further found that the slip system is determined by the stacking-fault energy rather than the layer spacing. The indentations with other different parameters were also performed, and the results further prove the validity of the conclusion.