Air Vice Marshal Sir Leonard Monk Isitt KBE (27 July 1891 – 21 January 1976) was a New Zealand military aviator and senior air force commander. In 1943 he became the first New Zealander to serve as the Chief of the Air Staff of the Royal New Zealand Air Force, a post he held until 1946. At the close of World War II, Isitt was the New Zealand signatory to the Japanese Instrument of Surrender. After the war, following retirement from the Air Force, he worked as chairman of Tasman Empire Airways.