Abstract: In view of the influence of traditional grinding methods on crankshaft accuracy and surface quality, a follow-up grinding method based on the headstock spindle with variable speed movement and constant speed feed of grinding wheel is proposed in this paper. By deriving the instantaneous position equation of follow-up grinding, the motion trajectory control model of follow-up grinding is established. The two grinding methods are compared by simulation analysis. The results show that the radius of the grinding wheel has little influence on the following grinding mode with variable spindle motion, the speed and stress state of the grinding point relative to the rotating center are more stable, and the surface processing quality of crankshaft is greatly improved.