He matriculated from St. Paul's High School, Rangoon in 1954, student ranking fifth in the country, and was awarded collegiate scholarship.
Than Nyun graduated in Economics from Rangoon University in 1958, Ph.D degree from Trinity College, Cambridge and Econ.
He served as chairman of the Union Civil Service Selection and Training Board (UCSTB) from 1999 to 2009.
[2] Than Nyun has traveled widely in Asia, Australia, Europe and the United States of America to participate in various conferences, meetings, seminars and other events.
He was deputy-leader of the Myanmar delegation to the World Summit for Social Development held in 1995 in Copenhagen.