The Płonia (German: Plöne) is a river in West Pomeranian Voivodeship, Poland, a right tributary of the Oder river, with a length of 74.3 km and a basin area of 1101 km2.

Its source is 1.5 south of Barlinek.

The river flows northwest through Miedwie and Płoń lake.

The upper portion of the Płonia is comparatively unpolluted, therefore trout can be found there.

This article related to a river in Poland is a stub.