Major-General Sir Walter Joseph Cawthorn CBE CIE CB (11 June 1896 – 4 December 1970) was an Australian soldier and diplomat, commonly known as a former head of the Australian Secret Intelligence Service (ASIS). Cawthorn was born in the suburb of Prahran in Melbourne. He enlisted in the Australian Imperial Force, following the start of World War I, and served as a regimental sergeant major, in Gallipoli. He was commissioned into the Indian Army in 1918. He was knighted in 1958, and appointed as high commissioner of Canada. Cawthorn died in Melbourne, at the age of 74.