Abstract: In order to obtain the friction characteristics of ground the structured fish scale surface. The topological structured fish scale surface is firstly designed, and then the hydrodynamic lubrication model of the surface is established, and the fluid simulation software is used for analysis. The oil film bearing capacity and friction coefficient of the ground unit fish scale dimples with different roughness are studied and compared, and the pressure and friction coefficient of the structured fish scale surface change with the oil film thickness are analyzed as a whole. The results show that the lower the ground roughness is, the better the lubrication effect of the structured fish scale surface unit is in the given range of structured surface parameters. Overall, the lubrication effect of the structured fish scale surface has a significant cumulative effect. The structured fish scale surface with proper parameters can improve the oil film bearing capacity and reduce the friction coefficient, thus improving the lubrication effect of friction pairs.