Abstract: By taking a typical planetary roller screw as the research object, a finite element model for dynamic contact of planetary roller screw was established. Based on explicit dynamic finite element method, a dynamic contact analysis of the planetary roller screw was made, a fully integration element algorithm was adopted to control hourglass, the computing speed was improve by adjusting the element density and using mixed time integration algorithm. It was concluded that the axial displacement and speed between screw and roller were raised as increasing in the rotational speed of roller; the dynamic von Mises stress of contact elements on thread teeth were basically the same in different rotational speeds imposed on roller; the phenomenon of loading uneven distribution was presented on whole planetary roller screw thread teeth at the same roller speed, besides, the dynamic von Mises stress fluctuation of the first thread tooth was bigger than others, and the dynamic von Mises stress of contact elements on screw side were bigger than nut side.