Chaharborj County () is in West Azerbaijan province, Iran. Its capital is the city of Chahar Borj, whose population at the time of the 2016 National Census was 9,406 in 2,793 households.
In 2021, Marhemetabad District was separated from Miandoab County in the establishment of Chaharborj County and renamed the Central District. The new county was divided into two districts of two rural districts each, with Chahar Borj as its capital and only city at the time.
Chaharborj County's administrative structure is shown in the following table.