Hoseynabad-e Khereh Sar () is a village in Ahmadabad Rural District of the Central District in Nazarabad County, Alborz province, Iran.
At the time of the 2006 National Census, the village's population was below the reporting threshold, when it was in Tehran province. In 2010, the county was separated from the province in the establishment of Alborz province. The 2016 census measured the population of the village as 16 in four households.