Arumugam Ponnu Rajah (7 July 1911 – 28 September 1999) was a Singaporean judge, diplomat and politician.

[5] He was later conferred the Honorary Degree of Doctor of Laws by the National University of Singapore (NUS) on 14 November 1984.

[10] In 1959, Rajah re-entered politics as an independent candidate[11] and was elected to the Legislative Assembly for Farrer Park.

[14] Rajah returned to Singapore in 1973 to resume legal practice, and was later appointed as a Supreme Court judge on 1 October 1976.

[4] Rajah was the Pro-Chancellor of National University of Singapore from 1990 to 1999[15] and was also chairman of the Hindu Advisory Board in that time.