Bone milling is a necessary step in craniotomy and orthopedic surgery,and excessive milling force can lead to problems such as milling cutter fracture and cracking around bone tissue,which can affect the surgical process.The ABAQUS simulation software was used to conduct finite element simulation of cortical bone milling with four-edge end milling cutter and to verify the correctness of the model.Based on the simulation model,a central composite experiment was designed.The quadratic regression equation of milling force was obtained by using response surface method,and the influence of milling speed,feed and milling depth on milling force was explored.The study results provide reference for the rational setting of milling parameters in orthopedic surgery,and quadratic regression equations as predictive model can provide possibility to control milling forces during surgery.