Abstract: With the development of green new energy vehicles, the demand for lithium battery copper foil is increasing. High-quality electrolytic copper foil is rather thin, and its quality is greatly affected by the surface state and internal stress of the cathode roller. In response to the need to improve the quality of copper foil of the domestic lithium battery copper foil integrated machine, the residual stress of its core component cathode roller was ultrasonically tested, the test point was verified by the blind hole method, and the welding, spinning and other process treatments were compared. The difference in the residual stress distribution on the surface of the cathode roll indicates that the three types of cathode rolls have different compressive stress states, which provides an important reference for product design. At the same time, in order to evaluate the stress relief process of the vibrating cathode roller, the ultrasonic method was used to test and evaluate the effect of vibration elimination of the residual stress on the cathode roller.