Laser polishing technology plays an increasingly important role in the material processing technology.In order to study the influence of scanning interval on the polishing effect of S136D die steel, the single factor experiment method is used in this paper. The continuous fiber laser is used to carry out many laser polishing experiments and the influence of laser scanning interval on the surface morphology of S136D die steel is analyzed.The results show that the surface roughness of polished samples decreases first and then increases with the of scanning interval. When the scanning interval is in the range of 0.03-0.1mm, the surface roughness of samples is relatively flat, and the lowest surface roughness can be reduced to 0.781μm, and the reduction rate of surface roughness can reach 90.2%.