Ij (Persian: ايج) is a city in the Central District of Estahban County, Fars province, Iran, serving as the administrative center for Ij Rural District.

At the 2006 census, its population was 6,233 in 1,497 households. The following census in 2011 counted 5,849 people in 1,622 households. The latest census in 2016 showed a population of 6,246 people in 1,876 households.