Zelgniewo [zɛlɡˈɲɛvɔ] is a village in the administrative district of Gmina Kaczory, within Piła County, Greater Poland Voivodeship, in west-central Poland. It lies approximately 11 kilometres (7 mi) north-east of Kaczory, 15 km (9 mi) east of Piła, and 87 km (54 mi) north of the regional capital Poznań. The population was 469 at the 2011 census.