The Thai nobility was a social class comprising titled officials (khunnang, Thai: ขุนนาง) in the service of the monarchy. They formed part of a hierarchical social system which developed from the time of the Ayutthaya Kingdom (14th century – 1767), through the Thonburi (1767–1782) and early Rattanakosin (1782 onwards) periods. Reforms by King Chulalongkorn ended the system around the end of the 19th century, though noble titles continued to be granted until the abolition of absolute monarchy in 1932.
Thai noble titles comprise a rank and a title, which denote the holder's post or office. Unlike in European aristocracies, Thai noble titles were not inherited, but individually granted based on personal merit. Nevertheless, familial influence was substantial, and some families were able to accumulate large amounts of wealth and power, especially during the 17th to 19th centuries.