 With a master's degree in economics from Patna University and a gold medal, Sinha joined the Communist Party of India in 1940 and served the party as state secretary.A lecturer and journalist, Sinha was Secretary of the Bihar State Council of the Communist Party of India from 1962 to 1967 and had served as the General Secretary of the All India Kisan Sabha from 1973 until the late 1990s.Sinha was also editor of the "Hunkar", "Janasakti" and "New Age" weeklies.