Samalqan District () is in Samalqan County, North Khorasan province, Iran. Its capital is the city of Qazi.
In 2013, two villages merged to form the new city of Ava.
At the time of the 2006 National Census, the district's population was 20,621 in 5,466 households. The following census in 2011 counted 22,335 people in 6,464 households. The 2016 census measured the population of the district as 21,378 inhabitants in 6,738 households.