Iranian migration to Thailand began as early as the 17th century. Thai citizens of Iranian background or descent may be called in Thai: Khaek Ma-ngon (Thai: แขกมะหง่น) or Khaek Chaosen (Thai: แขกเจ้าเซน "Shia Muslim")
During the Ayutthaya Kingdom period, the Iranian community in Thailand consisted primarily of merchants. They are recorded in some memoirs of their fellow merchants, the Dutch East India Company, as well as in the Ship of Sulaiman, an account of a Persian embassy to King Narai. Some descendants of Iranians from the Ayutthaya period converted to Buddhism, and continued to retain influence in Thai public life down to the present day; one prominent example is the Bunnag family, whose ancestor "Shaykh Ahmad" is said to have come from Qom and arrived at Ayutthaya in 1602.
In recent years, Thailand has become a popular destination for Iranian medical tourists. However, due to numerous incidents of methamphetamine smuggling, Iranians coming to Thailand fall under heavy suspicion from police.