Osłowo [ɔˈswɔvɔ] is a village in the administrative district of Gmina Mielnik, within Siemiatycze County, Podlaskie Voivodeship, in north-eastern Poland, close to the border with Belarus. It lies approximately 4 kilometres (2 mi) north-west of Mielnik, 13 km (8 mi) south-east of Siemiatycze, and 86 km (53 mi) south of the regional capital Białystok.
According to the 1921 census, the village was inhabited by 114 people, among whom 15 were Roman Catholic, 90 Orthodox, and 9 Mosaic. At the same time, 105 inhabitants declared Polish nationality, 9 Jewish. There were 20 residential buildings in the village.