Olszewo [ɔlˈʂɛvɔ] is a village in the administrative district of Gmina Śmigiel, within Kościan County, Greater Poland Voivodeship, in west-central Poland. It lies approximately 9 kilometres (6 mi) south-east of Śmigiel, 14 km (9 mi) south of Kościan, and 53 km (33 mi) south-west of the regional capital Poznań.