Penovsky District (Russian: Пе́новский райо́н) is an administrative and municipal district (raion), one of the thirty-six in Tver Oblast, Russia. It is located in the northwest of the oblast and borders with Ostashkovsky District in the north, Selizharovsky District in the east, Andreapolsky District in the south, and with Maryovsky District of Novgorod Oblast in the west. The area of the district is 2,385 square kilometers (921 sq mi). Its administrative center is the urban locality (an urban-type settlement) of Peno. Population: 6,864 (2010 Census); 8,523 (2002 Census); 10,291 (1989 Census). The population of Peno accounts for 61.5% of the district's total population.