Abstract: In order to achieve better finishing and strengthening effect on laser cladding layer of axle steel, ultrasonic rolling method was used to treat laser cladding layer of EA4T axle steel and its main machining parameters optimization was analyzed. The results show that the surface roughness of laser cladding increases with the increase of the reduction amount. With the increase of static pressure, the surface hardness of cladding layer firstly increases and then decreases. When the rolling rate is increased, the surface roughness of the sample decreases first and then increases. With the increase of rolling times, the surface hardness of the cladding layer increases first and then decreases. The optimal parameters were determined as follows: under the conditions of rolling down 0.10 mm, rolling rate 2100 mm/min, static pressure between 0.45~0.65 MPa and rolling three times, the ultrasonic rolling method could achieve excellent surface finishing effect. There are obvious plastic deformation layers on the surface of laser cladding layer after ultrasonic rolling. The plastic deformation degree of laser cladding layer decreases with increasing depth, while the grain size increases. According to the research results of this paper, it can provide a theoretical reference for the optimization of ultrasonic rolling process of laser cladding hot working axle steel, and provide theoretical guidance for the practical application process. In addition, it can also promote the improvement of die manufacturing technology and repair ability.