Abstract: Combining the oil mist lubrication with CFD has become an effective way to investigate the mechanism of oil mist lubrication. A CFD-based numerical simulation of oil mist flow field was therefore done to investigate the oil mist temperature field and lubrication effect in the bearing cavities of supporting rollers for continuous annealing/leveling system. The results revealed the heat transfer process of oil mist in bearing cavities under condition that the calorigenic rates of rollers are different. The fitted equations of roller's calorigenic rates and bearing temperature rising were thus given with two different supplies of lubricant, thus showing the influence of roller's calorigenic rate on lubrication effect and the ways to enhance the heat dissipation potential and decrease the temperature of the supporting rollers.