(Mid 14th to late 18th Centuries)
Architecture from this period can best be divided into four distinct sub-periods that span more than four centuries from 1350 to 1767.

   The first sub-period (1350 to 1488)
   The second sub-period (1448 to 1629)
   The third sub-period (1629 to 1732)
   The fourth sub-period (1732 to 1767)

The influence from Ceylon (now Sri Lanka) was thought to be quite strong throughout the second sub-period as was the obvious influence of Khmer architectural style during the third sub-period. A notable surviving building from the second sub-period is the beautiful Sri Lanka-style bell shaped chedi at Wat Phra Si Sanphet. During the third period the King sent architects to carefully study the characteristics of Khmer architecture and the prang once again became very popular in Ayutthaya. Good examples are at Wat Watthanaram, the corn-on-the-cob shaped prang at Wat Ratchaburana and Wat Chumphon at Bang Pa-In.

Most of the temples throughout the era had very elaborate structures with particularly ornate chufas, door and window pediments being common. Carved Buddha images were often featured in the niches of the prang structures. The Chedi mostly had ringed spires tapering to fine points.