Wat Si Muang or Simuong is a Buddhist temple located in Vientiane. The temple was built in 1563. Located near the eastern entrance to the city centre, on the road leading from the Friendship Bridge to Thailand, the small temple was built on the ruins of a Khmer Empire Hindu shrine, the remains of which can be seen behind the ordination hall. The location makes it perhaps the busiest temple in Vientiane.
Inside, the temple is unusual in being divided into two rooms. The first one is for blessings by the monks. The second houses the large main altar and numerous statues and images of Buddha.