Sushama Nath belonged to the 1974 batch of the IAS (MP Cadre). She served in both the State and Centre in various capacities in the finance, agriculture, food, water resources, and rural sectors as well as in culture, tourism, personnel, and general administration.
She also served as Secretary, of the Indian Council of Agricultural Research and Member Secretary of the Sixth Central Pay Commission. She was Secretary, of the Department of Expenditure, Ministry of Finance Government of India, and retired as Finance Secretary Government of India.
She was a Member of the Fourteenth Central Finance Commission and later served as a part-time Member of the Insurance Regulatory and Development Authority of India (IRDAI)