Kotmale Mahaweli Maha Seya, Buddhist stupa in Kotmale, Sri Lanka

Kotmale Mahaweli Maha Seya is a Buddhist stupa in Kotmale, Sri Lanka, rising 88 metres (289 ft) above the Kotmale Reservoir. Its structure was designed by Vidya-Jyothi Dr. A.N.S. Kulasinghe. At 88 metres it is the second-largest stupa in Sri Lanka, after Ruwanweli Maha Seya in Anuradhapura.

Gamini Dissanayake, then opposition leader and former Mahaweli Development minister, proposed the stupa to commemorate more than 50 temples submerged by the Mahaweli Development programme in the early 1980s. President J. R. Jayewardene laid the foundation stone on 20 March 1983. President Maithripala Sirisena and Prime Minister Ranil Wickramasinghe opened the completed stupa on 20 June 2016.

The stupa serves as a sacred place where Buddhist monks and devotees gather throughout the year to pray, meditate, and perform religious ceremonies. The structure itself holds deep spiritual meaning as a symbol of remembrance for the local community.

The stupa is accessible via nearby highways and local transportation options around the Kotmale Reservoir area. The site provides basic facilities for visitors, including spaces designed for meditation and religious activities.

The stupa's design was prepared by Vidya-Jyothi Dr. A.N.S. Kulasinghe, the engineer behind several major Sri Lankan projects. At 88 m (289 ft) it is Sri Lanka's second-largest stupa, after Ruwanweli Maha Seya in Anuradhapura, built in 140 BC. It was opened on 20 June 2016 by President Maithripala Sirisena and Prime Minister Ranil Wickramasinghe.