The Xiangkhouang Plateau or Tran Ninh Plateau is a plateau in the north of Laos. The landscape is characterized by green mountains, rugged karst formations and verdant valleys with plenty of rivers, caves and waterfalls. The highest peaks of the plateau are between 2000 and 2800 meters high (about 6561 and 9842 feet high). The highest mountain of Laos, Phou Bia, is located to the south of the plateau. Several tributaries of the Mekong originate in the Plateau, such as the Nam Ngum.
The plateau is the location of the Plain of Jars, which is a collective name for several sites with archeological remains nominated for UNESCO World Heritage status. The major town in the area is the capital of Xiangkhouang Province, Phonsavan.
The plateau is also one of the most heavily contaminated areas in the world from unexploded cluster munitions also called UXO.