Abstract: To simulate the process for the tilt manufacturing of spiral bevel gears based on five-axes Computer Numerical Control machine,check out the reliability of the equations of five axes linkages,and to get the geometry model of spiral bevel gear,this paper presents the theory of the spatial kinematics transformation between traditional machines and numerical control machines with five axes linkages.Based on the spatial kinematics transformation theory,it discusses and derives the equations of five axes linkages for the spiral bevel gear manufactured by milling process.Making use of Visual Basic Application programming language embedded in AutoCAD,we have developed a system of simulation processing based on five-axes CNC.In this system,modeling is driven by inputting the parameters of the work and the tool.It turns out that,the geometry model of spiral bevel gear is accurate enough for the follow-up treatment and the post-analysis,and the equations of five axes linkages are correct.It provides a clean and efficient way for geometry modeling of spiral bevel gear.