Olszyny [ɔlˈʂɨnɨ] is a village in the administrative district of Gmina Piątnica, within Łomża County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 11 kilometres (7 mi) east of Piątnica, 13 km (8 mi) north-east of Łomża, and 63 km (39 mi) west of the regional capital Białystok.