Abstract: Claw rotor determines the performance of the claw vacuum pump,and the profile is the basis of rotor design. In order to further improve the volume utilization rate of claw rotor and reduce the remaining gap volume,this paper establishes the meshing model of elliptical arc and its envelope based on the curve meshing theory,and then proposes a new elliptical arc rotor:a new elliptical arc straight claw rotor,analyzes its working content product ratio and volume utilization rate,and compares the clearance volume and closed volume. The results show that all curves of the elliptical arc straight claw rotor are smoothly connected,and the correct meshing effect can be achieved. The clearance volume and closed volume are reduced compared with the sharp point rotor and the arc rotor,and the content product ratio and volume utilization rate are higher.