Basanta Kumar Nembang started student politics in 2036 BS by being involved in a student union at the Nepal Law Campus.
He worked as the UML district committee member from 2048 BS to 2067 BS and became UML national representative council member in 2070 BS. Nembang served as the Minister for Physical Infrastructure and Transport in 2076 BS. He is currently a central committee member of CPN-UML.
Nembang was elected lawmaker in the House of Representatives elections held in 2048 BS, 2056 BS and 2074 BS. He is contesting the polls from Panchthar.