In the present investigation a phase field model was used to analysis the processing of grain nucleation, and the nano-liked interface effect was introduced to describe the influence of the nucleation from grain growth kinetics. The precipitation of nuclei, the change of the nuclei number, the thickness of grain boundary and the feature of grain growth were studied at the same time. The simulation results show that the interface effect provides the driving power for nuclei growth, and the number of nuclei increases with prolonging of time, the radii of nuclei increase and the growth of nuclei changes fast. The distribution of the radius orientation reflects the change of grain boundary thickness and the grain size