Marchelówka [marxɛˈlufka] is a village in the administrative district of Gmina Janów, within Sokółka County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 4 kilometres (2 mi) north-east of Janów, 19 km (12 mi) north-west of Sokółka, and 42 km (26 mi) north of the regional capital Białystok.