Wat Yom Mon is a defunct temple formerly located off the city island in the eastern area of Ayutthaya in the Hua Ro Sub-district.
The monastery was situated south of Wat Nang Chi, near Wat Yom Thai. The latter was located on the premises of the present Wat Tham Niyom.
A single monastic structure named Wat Yom is mentioned on Phraya Boran Ratchathanin's map drafted in 1926 CE. Phraya Boran (1871-1936 CE) was the Superintendent Commissioner of Monthon Ayutthaya from 1925 to 1929 CE but occupied important functions since 1896 CE in Monthon Ayutthaya.
Two monastic structures, Wat Yom Thai and Wat Yom Mon, feature on a 19th-century map.
Wat Yom Thai and Wat Yom Mon were situated about 200 meters from each other, following a Fine Arts Department (FAD) excavation map drafted in 2007 CE.
Wat Yom Thai stood south of Wat Yom Mon, identical as indicated on the 19th-century map.
Historical data about the monastery and its construction are unknown.
The 19th-century map indicates the existence of a chedi on its eastern side.
Based on the 2007 CE FAD map, the site was in geographical coordinates: 14° 21' 40.42" N, 100° 34' 54.31" E.
