The present volume is a romanized collation of four Pali manuscripts of the Jambupati-sutra, supplemented by Pali passages extracted from two old Thai-language versions. The Jambupat-sutra is a dramatic narrative that relates how the Buddha overcomes an arrogant and powerful king named Jambupati by conjuring up an illusory city with himself as king, in the end guiding the king to sainthood. Popular up to the early Ratanakosin period, the Jambupati-sutra is an outstanding example of the creative apocryphal Pali literature of Siam. This is the first time the Pali Jambupati-sutra has been published. A future volume will give a complete English translation and a literary, ritual, and social history of the sutra.