St. Mary's Orthodox Syrian Cathedral is an Orthodox ancient church located in Thumpamon near Pandalam, Kerala state of India. It is the headquarters of the Thumpamon Diocese of the Malankara Orthodox Syrian Church. The first church was built in AD 717. The Architectural style of the church is Gothic Revival style.

Thumpamon is a village in Pandalam, a part of Adoor thaluk in Kerala, India. One of the greatest attractions of this village is the Achenkovil River, which is known for its natural sceneries along the riverbank. The village relies on non-resident Indian and crops like rubber, coconut, paddy and pepper. The most common crop in the village is rubber. Because of non-resident Indians, this is one of the wealthiest villages in Kerala. Thumpamon is divided into two regions, Thumpamon North and Thumpamon South, by the Achenkovil River.