Abstract: The cutting temperature is an important factor affecting the life, wear and cutting efficiency of cutter.If the cutting temperature is too high, it will accelerate the thermal wear of cutter, reduce the life and the cutting efficiency.The cutting depth is an important parameter affecting the failure model of rock, which changes the stress state of cutter by changing the failure model of rock, and cutting force is the direct cause of cutting heat, cutting temperature rise, so cutting depth will have an impact on the change of cutter temperature field in the cutting process.Based on the rock cutting thermal model and Drucker-Prager as the rock strength criterion, the dynamic rock breaking model of the cutter was established to further study the effects of cutting forces, temperature distribution and the law of temperature rise of cutter at different cutting depths.The results show that there is a critical depth d^*, which changes the rock failure mode from plastic cutting to brittle cutting.The cutting force is proportional to the cutting depth during plastic cutting, the cutting force is nonlinearly related to the cutting depth during brittle cutting.The change of cutting depth will affect the temperature change of the back and the front of the cutter:the back surface temperature increases linearly with the increase of cutting depth and the temperature of front cutter surface increases first and then decreases with the increase of cutting depth.The increase of cutting depth makes cutting force fluctuations increase, thus causing the temperature fluctuations of the front and back flank to increase as the depth of cut increases.Through the simulation analysis of the stress state and temperature variation of the cutter under different cutting depths during the rock breaking process, it is found that the cutting depth has a significant influence on the temperature change of the cutter, and the theoretical analysis and the simulation results are basically consistent.