Krosinek [krɔˈɕinɛk] is a village in the administrative district of Gmina Połajewo, within Czarnków-Trzcianka County, Greater Poland Voivodeship, in west-central Poland. It lies approximately 5 kilometres (3 mi) north-west of Połajewo, 13 km (8 mi) south-east of Czarnków, and 49 km (30 mi) north of the regional capital Poznań.