The laser beam is affected by atmospheric turbulence during propagation, causing distortion of the light spot, affecting beam quality and in real life the turbulence varies with time. In this paper, a turbulent phase screen model based on the Fourier transform spectral inversion method is proposed to address above problem, and simulation research of laser propagation in dynamic atmospheric turbulence of different intensities is conducted by obtaining a dynamic phase screen based on the frozen-flow method. The simulation results show that for the same laser beam, the spot distortion increases with the increase of atmospheric turbulence intensity at the same time, and the received power density decreases overall with increasing undulations.