Laser cutting is considered as an effective tool to process the carbon fiber reinforced plastics (CFRP), but it is still a problem how to eliminate the heat affected zone (HAZ). In this paper, numerical simulation of laser cutting CFRP with different resin contents is carried out in order to investigate the formation mechanism and the effect of resin content on the HAZ. The energy distribution characteristics and heat transmission mechanism during laser cutting CFRP was studied through a finite element method. A model of laser-cutting of single-layer CFRP with different resin content was established by COMSOL multi-physics software to analyze the temperature field. The simulation results show that the absorbed laser energy is mainly transmitted along the direction of the carbon fiber laying. The maximum temperature of the surface carbon fiber in CFRP increases as the resin content increases. However, the width of HZA was decreases as the resin content increasing.