Mornai Tea Estate is a significant tea estate located in the Kokrajhar district of Assam, India, near the border of Assam and West Bengal. It is owned and managed by the Northern Evangelical Lutheran Church (NELC), a religious Christian organization. The estate was established in 1889 by Rev. Lars Olsen Skrefsrud and is an important economic asset for the NELC.

The estate is divided into five divisions: Mornai Main, Kalaghat, Paushpur, Thakurpur, and Grahampur, all situated close to each other. Its geography is constrained by two rivers, Moranai and Bao-nai, which also pose flooding risks to the lower banks where tea is grown. Mornai Tea Estate produces both Orthodox teas for international markets and CTC teas for domestic consumption, with quality and production considered notable.

The estate supports around 976 permanent employees and over 1310 temporary workers during peak seasons. It provides essential amenities such as hospitals, dispensaries, schools, water supply, sanitation, and weather protection gear for laborers. The estate is well-regarded for maintaining good living conditions and serves as an important economic and social institution for the surrounding community and the NELC church network.