Abstract：[Objectives] In order to grasp the influence of submarine acceleration and deceleration on wake characteristics in stratified flow, and to provide a theoretical basis for submarine stealth. [Methods] Using CFD technology, first verify the accuracy of the technology to simulate the motion of the submerged body to make waves on the free surface, and then analyze the wave making on the free surface, its convergence and divergence field, and the internal wave velocity field to accelerate and decelerate the real-scale submarine. Navigation simulation, through the divergence of the speed field of the free surface, in-depth study of the influence of submarine acceleration and deceleration on the free surface and the jump layer. [Results] The study shows that when the submarine is in unsteady motion, the shear wave and scattered wave distribution of the wake field are completely different from that of the uniform motion. Combining the wave height and velocity divergence field, the submarine acceleration and deceleration cause the free surface convergence and divergence effect. Difference; [Conclusions] When the submarine depth and stratification mode are the same, the wake field disturbance, wave height and roughness can be reduced when the submarine decelerates, and the acceleration state can significantly increase the probability of near-field disturbance and detection of the submarine.