Rydzewo-Pieniążek [rɨˈd͡zɛvɔ pjɛˈɲɔ̃ʐɛk] is a village in the administrative district of Gmina Radziłów, within Grajewo County, Podlaskie Voivodeship, in north-eastern Poland. It lies approximately 6 kilometres (4 mi) north-west of Radziłów, 23 km (14 mi) south of Grajewo, and 65 km (40 mi) north-west of the regional capital Białystok.