South Salmara-Mankachar district is a district in the state of Assam, India. It is situated in the westernmost part of Assam, sharing its borders with Bangladesh. The district was formed in 2016 when it was separated from the Dhubri district.

South Salmara-Mankachar district covers an area of approximately 750 square kilometers. The district is primarily rural in nature, with agriculture being the main occupation of the people. The region is known for its fertile agricultural lands and the cultivation of crops such as rice, jute, vegetables, and various fruits.