The Gibe River (also Great Gibe River) is by far the largest tributary of the Omo River in southwestern Ethiopia and flows generally south-southeast. The confluence of the Gibe River 8°19′N 37°28′E / 8.317°N 37.467°E with the smaller Wabe River forms the Omo River. The whole drainage basin is sometimes referred to as the Omo-Gibe River Basin with the Gibe and the Omo draining the (respectively) upper and lower reaches.
In common with most of Ethiopia's rivers, the Gibe is not navigable.