Abstract: In order to study the distributions of temperature field and thermal stress field, a threedimensional axial symmetric model of alumina ceramic was established. This paper described the thermal stress’s variation of the cutting point and studied the influence of laser power, ceramic thickness and cutting speed on the temperature field and thermal stress field. The model was validated by comparative experiments. The results show that with the increase of the tensile stress, the microcrack becomes deeper, which induces more surface particles to run off, then the roughness increases.