Zhangjiagang's 2025 population is now estimated at 775,312. In 1950, the population of Zhangjiagang was 3,112. Zhangjiagang has grown by 19,560 in the last year, which represents a 2.59% annual change.These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Zhangjiagang, which typically includes Zhangjiagang's population in addition to adjacent suburban areas.