Abstract: Al/Cu heterogeneous metal connection is the key process of developing and manufacturing new energy lithium-ion batteries with high energy density, high efficiency and long life. However, the thermophysical properties of aluminum and copper differ greatly and brittle intermetallic compounds are easily formed, so solid phase welding, such as ultrasonic welding, is considered to be one of the methods suitable for high-quality welding of aluminum and copper. With the rapid development of ultrasonic welding technology, the research on the ultrasonic welding of Al/Cu dissimilar metals has gradually changed from the feasibility of operation to the performance of Al/Cu welded joints. In order to further analyze the influencing factors on the properties of Al/Cu welded joints, based on the ultrasonic welding mechanism, the research status of Al/Cu ultrasonic welding was reviewed from the aspects of interface microstructure, intermetallic compounds, joint strength, etc. The effects of different welding parameters on the ultrasonic welding were summarized, the existing shortcomings of ultrasonic welding were pointed out, and its development prospects were reviewed.