As a typical Al-Zn-Mg-Cu series aluminum alloys, 7A52 aluminum alloy is widely used in the struc- ture of the aircrafts, rockets, light armored vehicles and ships with its excellent mechanical properties and high specific strength, which is often present in the form of weldments during practical applications. However, due to the low melting point of aluminum alloy, large heat transfer coefficient and high thermal expansion rate, when welded by conventional fusion welding process, this alloy may have such defects as weld cracks, pores and soft- ening of welded joints. Moreover, the unevenness of the welded joint is the main cause of failure in service. Therefore, how to improve the strength of the welded joint and realize the uniformity of the microstructure of the welded joint is one of the key problems in the welding of the high-strength aluminum alloy. The surface nan- otechnology is expected to solve this problem, thereby improving the overall performance of the welded joint. This paper reviews the research results at home and abroad in recent years. Based on the overview of 7A52 alu- minum alloy, it focuses on the comparison of the alloy TANDEM MIG, electron beam welding, friction stir weld- ing, laser welding, plasma welding and composite welding. At the same time, it discusses the research status of surface nanocrystallization of metal and its welded joints in details, especially elaborating the use of high-energy shot peening and ultrasonic impact treatment to achieve surface nanocrystallization and improve the current situ- ation and development trend of welding fatigue strength. It points out that improving the strength coefficient of joint is the key research direction of aluminum alloy welding in the future, and ultrasonic impact treatment tech- nology is one of the important methods to realize the nanometerization of welded joint surface.