Khansar County () is in Isfahan province, Iran. Its capital is the city of Khansar.
After the 2016 National Census, the village of Vist was elevated to the status of a city.
At the time of the 2006 census, the county's population was 31,542 in 9,394 households. The following census in 2011 counted 32,423 people in 10,186 households. The 2016 census measured the population of the county as 33,049 in 10,923 households.
Khansar County's population history and administrative structure over three consecutive censuses are shown in the following table.