Numerical analysis was carried out for elastohydrodynamic lubrication (EHL) of tapered roller considering moment balance. The equation of moment balance, corresponding to the discrete method and the formula of relative error were given. Position angle of roller changed with the relative error in order to satisfy the moment balance. When considering the moment balance, effects of load, velocity and half-tapered angle on the position angle of roller, pressure and film thickness were analyzed. Results showed that, if load is in the geometrical center of a roller, moment balance could be ignored for the EHL of cylindrical roller. However, it is very important for that of tapered roller. In order to satisfy the moment balance, the position angle of roller would be increased, and large end would be raised. The tiny variation of the position angle would cause severe changes of EHL of tapered roller. The numerical analyses considering moment balance are closer to the real working condition. Meanwhile, the effects are more obvious with the increasing of load, velocity and half-tapered angle.