With the advantages of rubber, the rotors of twin-screw air compressor with rubber coating were improved, and its mechanical properties were verified.3D modeling and assembly of the male and female rotors of the twin-screw air compressor were carried out by using SolidWorks software, and a pair of mutually meshing male and female rotors without rubber coating were obtained; the model of male and female rotors with rubber coating was established, and the geometric dimensions of the male and female rotors with rubber coating were guaranteed to be the same with the male and female rotors without rubber coating. The rotor torque was calculated and boundary conditions were set, then the male and female rotors without rubber coating and the male and female rotors with rubber coating were simulated through finite element analysis software respectively. The results show that the maximum equivalent stress of the rotors without rubber coating is 479.37 MPa and the maximum equivalent elastic strain is 0.002 7 mm; the maximum equivalent stress of the rubber-coated rotor is 318.25 MPa and the maximum equivalent elastic strain is 0.262 6 mm.The rubber coating can reduce the equivalent stress of the rotors and increase the equivalent elastic strain of the rotors. The results provide a new idea for increasing the service life of the rotor of the screw compressor, improving the air tightness and efficiency.