Thai literature is the literature of the Thai people, almost exclusively written in the Thai language. Most of imaginative literary works in Thai, before the 19th century, were composed in poetry. Prose was reserved for historical records, chronicles, and legal documents. Consequently, the poetical forms in the Thai language are both numerous and highly developed. The corpus of Thailand's pre-modern poetic works is large. Thus, although many literary works were lost with the sack of Ayutthaya in 1767, Thailand still possesses a large number of epic poems or long poetic tales —some with original stories and some with stories drawn from foreign sources. There is thus a sharp contrast between the Thai literary tradition and that of other East Asian literary traditions, such as Chinese and Japanese, where long poetic tales are rare and epic poems are almost non-existent. The Thai classical literature exerted a considerable influence on the literature of neighboring countries in mainland Southeast Asia, especially Cambodia and Burma.

Thailand, officially the Kingdom of Thailand and historically known as Siam, is a country in Southeast Asia on the Indochinese Peninsula. With a population of almost 70 million, it spans 513,120 square kilometres (198,120 sq mi). Thailand is bordered to the northwest by Myanmar, to the northeast and east by Laos, to the southeast by Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the southwest by the Andaman Sea; it also shares maritime borders with Vietnam to the southeast and Indonesia and India to the southwest. Bangkok is the state capital and largest city.