When pulsed laser is used to clean insulators, the distribution characteristics of surface pollution are different, and the distribution of overall temperature and stress field are also different. This paper takes porcelain insulator and its surface pollution as the object, establishes the finite element model, analyzes the temperature field and stress field respectively for the surface non-uniform distribution and uniform distribution of porcelain insulator pollution, and verifies the cleaning effect by laser experiment. The results show that when the energy density is 1.41 J/cm2 and the scanning speed is 1 000 mm/s, the non-uniform pollution on the laser irradiation path can be completely removed, and the removal rate of the uniform distribution of pollution is affected by the thickness and focal length position. The larger thickness, means the closer the distance from the focus, causes the higher the temperature rise, the greater the tensile stress, and the higher the clearance rate. The smaller thickness, means the farther away from the laser focal length, causes the lower the pollution clearance rate. Therefore, the incident distance and laser power should be adjusted timely when cleaning uneven distribution of pollution. The results show that the laser cleaning is the most efficient and the surface is smooth and clean. In the other two cases, there is residual pollution on the surface.