Abstract: A three-dimensional heat transfer model of the hydrostatic mechanical seals was established considering the misalignment of the stator. The governing equations, considering the variation of dynamic viscosity to fluid pressure and temperature variations, were numerically solved by using finite difference method. The effects of stator’s misalignment, heat convection coefficients and operating conditions on the temperature distribution of such a mechanical seal were studied. It is found that the maximum film pressure and the maximum temperature increased as the misalignment of the stator increased, and the effect of pressure-viscosity became more obvious when the misalignment became larger. Face temperature rises were affected obviously by operating conditions as well as stator’s misalignment and stator’s coning angle. A larger coning angle resulted in a lower face temperature rise and a lower temperature of the inlet fluid led to a higher face temperature rise. A higher velocity of the rotator led to a higher face temperature rise.