In this paper,an abrasive water jet surface descaling device for round steel is introduced,and the effect of abrasive concentration on surface descaling of round steel is studied.The water jet surface descaling experimentation of round steel was carried out,in which suitable abrasive was added into water jet in different proportion.The surface descaling effect of round steel was compared,and it has been proved that when water jet with garnet fineness of 80 mesh 50% is used the effect of surface descaling is best.The result of numerical computation corresponded with the experiment.