Naghan District () is in Kiar County, Chaharmahal and Bakhtiari province, Iran. Its capital is the city of Naghan.
In 2007, Kiar District of Shahrekord County, and Mashayekh and Naghan Rural Districts, and the city of Naghan, were separated from Ardal County in the establishment of Kiar County, which was divided into two districts and five rural districts, with the city of Shalamzar as its capital.
At the time of the 2011 National Census, the district's population was 15,507 people in 3,955 households. The 2016 census measured the population of the district as 15,957 inhabitants living in 4,695 households.