The wear of the star wheel tooth in single screw compressors increases the clearance, which reduces the volumetric efficiency and the service life. Robust liquid film lubrication between the meshing pair could prevent the tooth flank from contacting the groove flank, which would reduce the wear of the tooth and extend the lifespan of the compressor. This paper establishes two liquid film lubrication models between the tooth flank and the screw groove, one that takes inertial effects into account and another that does not. Meanwhile, a method for calculating load-carrying capacity and frictional force is proposed. The liquid film lubrication performance is compared across different rotating speeds, minimum clearances, and angles. The findings indicate that the convergence zone on the tooth flank generates dynamic pressure effects, significantly enhancing the load-carrying capacity. For relative sliding speeds below 40 m/s, the average liquid film pressure differs by 10.7% between models. For speeds exceeding 40 m/s, pressure calculations that account for inertia provide greater accuracy. An increase in rotating speed consistently elevates the load-carrying force in both models, but the variation in frictional force differs significantly. As the minimum clearance increases, both the load-carrying force and frictional force decrease. As the rotating angle varies, the load-carrying force and frictional force exhibit periodic fluctuations. However, estimates of the frictional force from the inertia-included model are less accurate. The research results are valuable for improving the lubrication design of the star wheel profile in single screw compressors.