Deraz Ab () is a village in Pol Khatun Rural District of Marzdaran District in Sarakhs County, Razavi Khorasan province, Iran.
At the time of the 2006 National Census, the village's population was 225 in 44 households. The following census in 2011 counted 188 people in 49 households. The 2016 census measured the population of the village as 241 people in 61 households.