Mazayjan (Persian: مزايجان) is a city in, and the capital of, Mazayjan District of Bavanat County, Fars province, Iran. It also serves as the administrative center for Mazayjan Rural District.

At the 2006 census, its population was 3,321 in 899 households, when it was a village in Mazayjan Rural District of the Central District. The following census in 2011 counted 3,041 people in 927 households, by which time the rural district had been separated from the district in the establishment of Mazayjan District. The latest census in 2016 showed a population of 3,567 people in 1,193 households, when the village of Mazayjan had been elevated to the status of a city.