Niwa [ˈɲiva] is a village in the administrative district of Gmina Grębów, within Tarnobrzeg County, Subcarpathian Voivodeship, in south-eastern Poland. It lies approximately 3 kilometres (2 mi) south-east of Grębów, 16 km (10 mi) east of Tarnobrzeg, and 59 km (37 mi) north of the regional capital Rzeszów.