Khagen Das was with the Tripura Legislative Assembly for a decade between 1978 and 1988. And then was the Chairman, Public Accounts Committee, Tripura State Legislature. Between 1983-88, he became the Cabinet Minister - Revenue, Health, Statistics, Printing & Stationery Tripura. In 1998 he became member of Rajya Sabha. In 2002, he was elected to the 13th Lok Sabha.