Abstract: In order to reveal the distribution of temperature field, the absorption and transfer of energy, and the formation mechanism of heat affected zone during laser cutting carbon fiber reinforced plastics, the carbon fiber reinforced plastics was chosen as the research object, and the multiphysics model of laser cutting carbon fiber reinforced plastics was established. The temperature field distribution during laser cutting and the influence of laser parameters on carbon fiber reinforced plastics temperature and heat affected zone were calculated. The 3-D temperature field distribution during laser cutting carbon fiber reinforced plastics was then obtained. The results show that the surface temperature field of carbon fiber reinforced plastics is approximately elliptical during laser cutting.The energy transfer and diffusion in carbon fiber reinforced plastics are mainly along the direction of carbon fiber laying. When the laser power is 20W, the spot radius is 100μm, and the laser with a cutting speed of 50mm/s is cut perpendicular to the carbon fiber laying direction, the carbon fiber temperature at the laser spot is much lower than the temperature of the resin layer. With the increase of spot radius and laser power, the maximum temperature in carbon fiber reinforced plastics increases gradually, and the heat affected zone gradually increases. With the increase of cutting speed, the maximum temperature in carbon fiber reinforced plastics gradually decreases, and the heat affected zone gradually becomes smaller. This study provides theoretical guidance for understanding the thermal damage mechanism of laser cutting carbon fiber reinforced plastics and the high quality and efficient processing of materials.