The Usno River is a tributary of the Omo River in Ethiopia. Formed by the confluence of the Magi and the Neri rivers, it flows south past the Nyalibong Hills before entering the Omo at 5°27′0″N 36°13′17″E / 5.45000°N 36.22139°ECoordinates: 5°27′0″N 36°13′17″E / 5.45000°N 36.22139°E. Almost all of the Usno's course is inside the boundaries of the Mago National Park.