With the crankshaft main bearing of internal combustion engine as the research object,based on the Reynolds equation and Greenwood-Tripp asperity contact theory,and by considering crankshaft misalignment and elastic deformation,the elastohydrodynamic lubrication model was established to analyze the influence of different journal profile on the lubrication of the main bearing.The results show that the influence of different journal profiles on lubrication characteristics of the main bearing is obviously different.Compared with the unprofiled case,when the journal profile is convex profile,the minimum oil film thickness of the main bearing is increased by 3812%,the maximum oil film pressure is decreased by 3273%,the average friction power loss is decreased by 84%,and the crankshaft inclination is improved.When the journal profile is saddle profile,the minimum oil film thickness of the main bearing is decreased by 2464%,the maximum oil film pressure is increased by 456%,the average friction power loss is increased by 2%,and the crankshaft inclination is intensified.When the journal profile is convex profile,the minimum oil film thickness and the average friction power loss are decreased,and the maximum oil film pressure is increased with the increasing of crankshaft misalignment angle,the minimum oil film thickness and the average friction power loss are increased,and the maximum oil film pressure is decreased with the increasing of the rotational speed.