Wat Ko Noi, or the Monastery of the Little Island, was situated off the city island in the southeastern area of Ayutthaya, in the Ko Rian Sub-district.
It is part of a cluster of three monasteries, the other two being Wat Kamphaeng (mound) and Wat Sangkhawat (mound), situated on the west bank of Khlong Ban Krot running parallel with the present Chao Phraya River and east of the railway Ayutthaya - Bang Pa-In.
In situ is only a mound encroached by vegetation.
Its historical background and period of construction are unknown.
The temple is only indicated on Fine Arts Department maps.
The site is in geographical coordinates: 14° 19' 42.47" N, 100° 35' 9.38" E.
