Thanchaiyan Srisuwan (Thai: ธารไชยยันต์ ศรีสุวรรณ) is a Thai military official, formerly serving as Thailand's Chief of Defence Forces, following his appointment by King Vajiralongkorn in September 2017, in an annual military reshuffle of senior officers.

Prior to his appointment, he served as chief of joint staff.

[1][2][3] Thanchaiyan studied at Wat Rajbopit School and then attended the Armed Forces Academies Preparatory School as a pre-cadet as a prerequisite for attending Chulachomklao Royal Military Academy (CRMA).

After graduating in Military school, he studied at Command and General Staff College and Joint Services Command and Staff College in England.

[4][5] Thanchaiyan previously held a position in the Royal Thai Army as the Commander of the 1st Cavalry Squadron, 1st Cavalry Regiment, King's Guard and moved to Royal Thai Armed Forces Headquarters as Head of Military Operations of Royal Thai Armed Forces and then Chief of Staff to the Royal Thai Armed Forces.