Leslie was born on April 7, 1920 in St Heliers, Auckland, New Zealand. He enlisted on March 5, 1941 aged 19, with the service number NZD 2435. He was 5' tall, with fair hair and blue eyes.
His service included the lighthouse tender HMNZS Matai, HMS Achilles; Kahu, Philomel, HMNZS Gambia, Philomel, the cruiser HMNZS Bellona, Tamaki and was a Petty Officer, cook. He left the navy on April 2, 1947.
After his service he was a baker and later a storeman. Leslie passed away on January 31, 1985 aged 64 at Glendowie, Auckland, New Zealnd of cardiovascular disease. He was cremated at Purewa Cemetery and Crematorium, Auckland and his ashes scattered at sea.