The Nam Xan River (French: Nam Sane) is a major river of western-central Laos. It flows down from the mountains of central Laos, flows through Borikham and joins the Mekong river at 18°22′36″N 103°39′29″E / 18.37667°N 103.65806°E / 18.37667; 103.65806 at Paksan.
