Diwaniyah's 2025 population is now estimated at 610,804. In 1950, the population of Diwaniyah was 22,854. Diwaniyah has grown by 19,280 in the last year, which represents a 3.26% 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 Diwaniyah, which typically includes Diwaniyah's population in addition to adjacent suburban areas.