The simulation of nanoindentation into single nickel crystal is performed by using quasi continuum method.The strain energy-displacement and load-displacement curves are presented to study the mechanical behavior of the dislocation nucleation.The characteristics of the stacking fault and dislocation nucleation are determined by calculating the centro-symmetry parameters and analyzing the displacement field of the atoms beneath the indenter.The structure of the stacking fault and the characteristics of dislocation obtained in the simulation by quasicontinuum method are reproduced in the simulation by molecular dynamics. The simulation of nanoindentation into single nickel crystal is performed by using quasi continuum method. The strain energy-displacement and load-displacement curves are presented to study the mechanical behavior of the dislocation nucleation. The characteristics of the stacking fault and dislocation nucleation are determined by calculating the centro-symmetry parameters and analyzing the displacement field of the atoms beneath the indenter. The structure of the stacking fault and the characteristics of dislocation obtained in the simulation by quasicontinuum method are reproduced in the simulation by molecular dynamics.