Objective To summarize the occurrence mechanism of backside wear, the method of evaluating backside surface damage, the relationship between backside wear and osteolysis in acetabulum, and the approach to reduce backside wear in total hip arthroplasty with modular acetabulum prosthesis. Methods The recent articles about the backside wear in acetabular liners were extensively reviewed. Results Backside wear in acetabular liners is connected with micromotion between the liner and the shell, rough interface, thickness of the liner, and impingement. The methods to evaluate backside wear damage are only proceeded in revised acetabular liners. Backside wear can generate polyethylene particles that is likely related to the process of osteolysis in acetabulum through the screw holes of metallic shell. To reduce backside wear between the liner and the shell, measures such as improved locking mechanisms, smooth inner metallic shell, maximized shell liner conformity, improving the quality of polyethylene, and reducing impingement can be taken. Conclusion There is no method of evaluating the backside wear in vivo. The relationship between backside wear and osteolysis in acetabulum as well as aseptic loosening of acetabulum prosthesis is controversial.