Abstract: Based on the Reynolds model and mass-conserving boundary condition (JFO model), two numerical cavitation models for radial grooved face seals were developed. The steady, incompressible, polar coordinate Reynolds equation with the consideration of centrifugal effects and cavitation was discretized using the control volume finite method and then was solved using Gauss-Siedel relaxation iterative algorithm. The effects of two different cavitation models on seal performances were investigated. The results indicate that, in the radial grooved face seals situation, Reynolds model obviously underestimates the cavitation area, leading to inaccuracies in the estimation of several variables, such as open force, friction torque and leakage. This suggests that only mass-conserving model should be used when dealing with radial grooved face seals.