Maj-Gen (R) Iskandar Mirza had the shortest tenure as Governor-General of Pakistan. his period was from 6 October 1955 to 23 March 1956 (5 months 17 days) after that he became the First President of Pakistan (23 March 1956 to 27 October 1958)
Muhammad Ali Jinnah First Governor General. his period was from 14 August 1947 – 11 September 1948 (1 year, 28 days)