Abstract: The "2023.7.21" heavy rainstorm is the strongest rainfall in Putuo District of Shanghai in recent years.It is characterized by high rainfall intensity and short-term concentration, and there are different degrees of ponding in the eastern and southern areas of the area.This paper introduces the prevention and countermeasures of the"2023.7.21"heavy rainstorm, as well as the problems existing in the process of dealing with extreme rainfall, summarizes the experience and practices, and puts forward measures to improve the work of Putuo District in dealing with extreme rainstorm.