John Leak, VC (c. 1892 – 20 October 1972) was an Australian recipient of the Victoria Cross, the highest award for gallantry in battle that could be awarded at that time to a member of the Australian armed forces. Leak enlisted in the Australian Imperial Force in early 1915, and served with the 9th Battalion in the Gallipoli Campaign during the First World War. Evacuated suffering from dysentery, Leak rejoined his battalion after it had been withdrawn to Egypt. Along with his unit, he transferred to the Western Front in France and Belgium, where he participated in the Battle of Pozières in July 1916. He was awarded the Victoria Cross for his actions during the battle. The following month he was seriously wounded in the Battle of Mouquet Farm.
Leak was evacuated to the United Kingdom, and did not return to his unit until October 1917. Suffering from the effects of his service, Leak was convicted of desertion by a court-martial in November, but his sentence was ultimately suspended, and he returned to the 9th Battalion. In early March 1918 he was gassed, and did not rejoin to his unit until the Armistice of 11 November 1918. He returned to Australia and was discharged in 1919.
After jobs in Queensland, New South Wales, South Australia and Western Australia over the next twenty years, Leak settled in South Australia in 1937. He was severely affected by his war experiences, and was very reticent to discuss his VC exploits. He did not talk about his service, even to his family, until very late in life. He died in October 1972 and is buried in Stirling, South Australia.