Kiersnówek [kʲɛrsˈnuvɛk] is a village in the administrative district of Gmina Brańsk, within Bielsk County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 4 kilometres (2 mi) south-east of Brańsk, 22 km (14 mi) west of Bielsk Podlaski, and 47 km (29 mi) south-west of the regional capital Białystok.