Three Pagodas Pass (, pronounced 'Darn Chedi Sam Ong') is a pass in the Tenasserim Hills on the border between Thailand and Burma, at an altitude of 282 metres above sea level. The pass links the town of Sangkhlaburi in the north of Kanchanaburi Province, Thailand, to the town of Payathonsu in the south of Kayin State, Burma.

This pass has been the main land route into western Thailand since ancient times, and is believed be the point at which Buddhist teachings reached the country from India in the 3rd century. During the Ayutthaya period in Thai history (14th-18th centuries), the pass was the main invasion route for the Burmese, but was also occasionally used toward Burma by Thai armies. The three small, crumbling pagodas, or chedis, after which the pass is named were probably built at the end of this period as a symbol of peace. They are now on the Thai side of the border. Parts of the border are still disputed.

During World War II, Japan built the infamous Death Railway (officially Taimen -
Rensetsu Tetsudo) through the pass. There is a memorial here to commemorate the Australian prisoners of war who (with many other Allied soldiers and Asian civilians) died as forced labourers during the construction of the railway.

The area is home to a number of hill tribes, including Karens, Mons and Burmese, who are unable or unwilling to obtain citizenship of either of the neighbouring countries. Since the end of World War II, there have been regular attempts by rebel armies to take control of the pass from Burma, with the Mon group in effective control until 1990, when Burma regained control. There are also occasional skirmishes between Karen and Mon rebel groups.

Nowadays, the pass is popular with tourists who, subject to the occasional hostilities between the two countries, are allowed to obtain a one-day visa from the Thai side to visit Payathonsu. Tourist attractions on the Burmese side include the locally made wooden furniture, jade carvings, and textiles.