 In the reign of King U Thong of Ayutthaya it was named "Mueang" Pak.When King Narai the Great built "Mueang" Nakhon Ratchasima as the northeastern frontier city of Ayutthaya, "Mueang" Pak was a frontier city of Nakhon Ratchasima, then called "Dan Chapo" (ด่านจะโปะ).King Taksin the Great changed the name of the city to Pak Thong Chai and set aside this area for Lao people from Vientiane kingdom.