The crown wall is a crucial part of sloping revetment，being used to reduce the wave impact on the backfilling structure behind the wall. As an important force influencing the stability of wave walls，estimation of wave forces is always a hotspot of research in engineering practice. Taking a sloping revetment of an artificial island project in Southeast Asia as an example，we analyze the three widely used calculating methods for wave force acting on crown walls，proposed by Coastal Engineering Manual and The Rock Manual，and a recently proposed method using overtopping results to estimate wave forces. We also compare and analyze the features and application scope of these methods based on an actual project，and compare the results of the 2D physical model test of this project with the calculating results of the four methods. The results show that Pedersen formula gives more close results to the actual measurement results，which can provide good references for similar projects.