Uniaxial tensile deformation simulation of nanocrystalline was performed using the phase-field-crystal (PFC) method coupling with strain, including the motion of high-angel boundary and low-angel boundary and the mechanism of grain growth. Simulation results show that in the process of uniaxial tensile deformation, the stress induces grain growth. There exists two mechanisms which are GB migration and grain rotation, and they both influence and interact each other. Since the motion of dislocation of low-angel GB results in grain rotation, grains have merged each other. Curvature-driven high-angle GBs migration shows that high-energy GBs are disappearing and low-energy GBs are growing. Moreover in the process of GBs motion, when the grain size is small enough, it will arouse grain rotation and stimulate grain growth