Abstract: Based on the statics analysis of double row four-point contact ball bearings,the numerical calculation model of the friction torque between the rolling elements and the raceways are obtained. The theoretical analysis for the effects of the load conditions,geometry parameters on friction torque of the double row four-point contact ball bearings are presented. The results showed that in order to decrease the friction torque and heat,and improve the life,the bearing is preferably operated at lower tilting moments,and the geometry parameters of the double row four-point contact ball bearings should be selected as following:the nominal contact angle nearly50°,groove curvature radius factor 0.53-0.54,clearance 0～-0.05 mm and smaller pitch diameter of ball set.