Muang Soui(In Lao: ເມືອງສຸຍ) (also called Muang Souy or Muong Soui) is a small town in Xiangkhouang Province Laos. It is located on Route 7 of Laos, so east of Phoukhoune district, northwest of Phonsavan, and Ban Phou Pheung Noi, but north of Sam Thong, and Long Tieng.