Hwaseong Fortress or Suwon Hwaseong is a fortification surrounding the centre of Suwon, the provincial capital of Gyeonggi Province, in South Korea. It was built from 1794 to 1796 by King Jeongjo of the Joseon dynasty to house and honour the remains of his father, Prince Sado. Sado had been executed by being locked alive inside a rice chest by his own father King Yeongjo after failing to obey a command to commit suicide. Located 30 kilometres (19 mi) south of Seoul and enclosing much of central Suwon, the fortress includes King Jeongjo's palace Haenggung. The fortress and enclosed palace were designated as a World Heritage site by UNESCO in 1997. It comprises among many other features the palace, a perimeter wall, four main gates, and two sluicegates over the Suwoncheon, Suwon's main stream, which flows through the centre of the fortress.

Korean fortresses are fortifications constructed by Koreans since the Three Kingdoms of Korea period. Koreans developed a unique and distinct fortress tradition. Korea, beginning with Goguryeo, has been called "a country of fortresses"; almost 2,400 mountain fortress sites have been found in Korea.