Kapetan Mitrousi () is a former municipality in the Serres regional unit, Greece. Since the 2011 local government reform it is part of the municipality Serres, of which it is a municipal unit. It is located in the west-central part of the Serres regional unit and has a population of 4,125 inhabitants (2021 census) and a land area of 87.485 kmò. The seat of the municipality was the town of Provatas (pop. 829). Its other communities are Mitroúsi (pop. 1,599), Anagénnisis (523), ÃÂno KamÃÂla (546), Vamvakiá (395) and Monokklisia (233).