Coordinates: 48°23′19″N 2°57′26″E / 48.38861°N 2.95722°E / 48.38861; 2.95722

The Yonne is a river in the northern half of France. It flows mainly through the western part of the Bourgogne-Franche-Comté region, giving its name to the Yonne department and to several communes. It is the main left tributary of the Seine river.

The river was named during the Roman Empire as Icauna, a Latin word that likely came from the Celtic name for the river.