Osieczek [ɔˈɕɛt͡ʂɛk] is a settlement in the administrative district of Gmina Dobiegniew, within Strzelce-Drezdenko County, Lubusz Voivodeship, in western Poland. It lies approximately 5 kilometres (3 mi) west of Dobiegniew, 16 km (10 mi) north-east of Strzelce Krajeńskie, and 41 km (25 mi) north-east of Gorzów Wielkopolski.