List of Thai monarchs

King of Thailand
พระมหากษัตริย์ไทย
Royal Standard of Thailand (since 1910)
Incumbent
Vajiralongkorn (Rama X) since 13 October 2016
Details
Style	His Majesty
Heir presumptive	Dipangkorn Rasmijoti
First monarch	Si Inthrathit of Sukhothai
Formation	1238
Residence	Grand Palace (official) Dusit Palace (private)
Website	Royal Office

The succession of Thai monarchs began with Si Inthrathit at the establishment of the first Thai kingdom in 1238. With brief interruptions, 55 monarchs have ruled over four successive kingdoms, the current monarch being Vajiralongkorn (Rama X) of the Chakri dynasty.