Deb Mukharji was a member of the Indian Foreign Service from 1964 to 2001, serving in various capacities in Indian Missions in Switzerland, Pakistan, Germany and Bangladesh, besides at headquarters on several assignments, including a deputation to the Department of Economic Affairs. He is an alumnus of the National Defence College.
He also served as Consul General, San Francisco (1983-1986), High Commissioner to Nigeria (1986-1989), High Commissioner to Bangladesh (1995-2000) and Ambassador to Nepal (2000-2001).