The Avre () is a river in Picardy, France, and is the principal tributary, from the left side, of the River Somme.
At long, it drains a relatively important basin of 1,150 km<sup>2</sup> but only flows at best 5.1 m<sup>3</sup>/s near its confluence at Longueau.<br> Its principal tributaries are: the Noye, joining at Boves, the Trois Doms joining at Pierrepont-sur-Avre, the Brache joining at Braches and the Luce at Berteaucourt-les-Thennes.