In this article,the effect of the bearing elastic deformation on the performance characteristics of a cylindrical journal bearing is analyzed.The variety of simulation models covers hydrodynamic(HD) and elastohydrodynamic(EHD) lubrication theories.The Reynolds equations governing the flow in the clearance space of the journal bearing are obtained by considering the effect of mass transfer across the fluid film.The finite element method with an iteration scheme was employed to solve both the Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing shell.The converged solutions for the lubricant flow and elastic deformation vector are obtained.Dynamic characteristics of the journal bearing are computed for HD and EHD theories.Numerical simulation results show that the flexibility of bearing liner has a significant influence on the performance of a cylindrical journal bearing.Indeed,the elastic deformations of the bearing liner extend the pressure area in the bearing and increase the minimum film thickness.Although,dynamic coefficient,load capacity and attitude angle decrease. In this article, the effect of the bearing elastic deformation on the performance characteristics of a cylindrical journal bearing is analyzed. The variety of simulation models covers hydrodynamic (HD) and elastohydrodynamic (EHD) lubrication theories. The Reynolds equations governing the flow in the clearance space of the journal bearing are obtained by considering the effect of mass transfer across the fluid film.The finite element method with an iteration scheme was employed to solve both the Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing shell Dynamic converging solutions for the lubricant flow and elastic deformation vectors are obtained. Dynamic characteristics of the journal bearing are computed for HD and EHD theories. Numerical simulation results show that the flexibility of bearing liner has a significant influence on the performance of a cylindrical journal. bearing.Indeed, the elastic deformations of the bearing liner ext end the pressure area in the bearing and increase the minimum film thickness .Although the dynamic coefficient, load capacity and attitude angle decrease.