Ong Keng Yong (born 6 January 1954) is a Singaporean diplomat who served as the Secretary-General of the Association of Southeast Asian Nations (ASEAN) from 2003 to 2007, and as Singapore's High Commissioner to Malaysia from 2011 to 2014.
Thereafter, he took over from Ambassador Barry Desker and assumed the position of Executive Deputy Chairman of the S.
Rajaratnam School of International Studies of Nanyang Technological University.