Gmina Poświętne is a rural gmina (administrative district) in Wołomin County, Masovian Voivodeship, in east-central Poland. Its seat is the village of Poświętne, which lies approximately 12 kilometres (7 mi) east of Wołomin and 30 km (18 mi) north-east of Warsaw.
The gmina covers an area of 106.26 square kilometres (41.0 sq mi), and as of 2006 its total population is 5,849 (6,081 in 2013).
Gmina Poświętne contains the villages and settlements of Choiny, Cygów, Czubajowizna, Dąbrowica, Helenów, Jadwiniew, Józefin, Kielczykowizna, Kolno, Krubki-Górki, Laskowizna, Małków, Międzyleś, Międzypole, Nadbiel, Nowe Ręczaje, Nowy Cygów, Ostrowik, Poświętne, Ręczaje Polskie, Rojków, Trzcinka, Turze, Wola Cygowska, Wola Ręczajska, Wólka Dąbrowicka and Zabraniec.
Gmina Poświętne is bordered by the town of Zielonka and by the gminas of Klembów, Stanisławów, Strachówka, Tłuszcz and Wołomin.