Abstract: The oil film thickness prediction plays an important role in evaluating the performance and durability of angular contact ball bearings (ACBB) under elastohydrodynamic lubrication (EHL). Coupling the quasi-static theory and the elliptical contact EHL model with spinning, based on the quasi-static analysis methods of dry contact, a quasi-static analysis model of ACBB considering EHL and spin motion of steel ball was established under constant and rigid preload methods. The Fast Fourier Transform (FFT) method was used to calculate the elastic deformation for elliptical contact. Then Gauss-Seidel iteration method was used to solve the Reynolds equation, and the completely numerical solution of the spinning EHL model was obtained, which was substituted into the bearing quasi-static model iteratively. As a result, the bearing internal contact load, three-dimensional (3D) contact pressure and 3D film thickness distribution were obtained. The analysis of SKF7210 ACBB under different preload methods shows: under flooded lubrication condition, when the bearing speed increased from 0 to 15000 r/min, the axial displacement of the inner ring decreased by 17.83% under constant force preload, while the axial load on the inner ring increased by 23.17% under fixed position preload. The film thickness between the ball and the inner and outer raceways with constant preload was slightly larger than that with fixed position preload. In addition, the central film thickness on the outer ring was 10% greater than that on the inner ring under different preload methods. Moreover, the contact load considering EHL under constant force preload was slightly larger than that of dry contact by 0.64%.