"Khe Sanh" is an Australian song, released as a 45 rpm single in May 1978, and named after the district capital of Hướng Hóa District, Quảng Trị Province, Vietnam. The song, performed by Cold Chisel, having been written by pianist Don Walker and featuring the vocals of Jimmy Barnes, is about an Australian Vietnam veteran dealing with his return to civilian life. According to Toby Creswell's liner notes for the band's 1991 compilation album Chisel, the song is also a story of restless youth.

The mood of the song is typified by its first verse:

The remaining verses describe the singer's aimless drifting after his return to Australia: womanising, post traumatic stress disorder, addiction to speed and Novocaine, getting work on oil rigs and flying helicopters. He has travelled the world: "I've been back to South East Asia but the answer sure ain't there". The final refrain is "Well the last plane out of Sydney's almost gone", as the singer heads to Hong Kong for casual sex.

Don Walker has said the song was inspired by a number of people, including, "the guy from the next farm," who came back from Vietnam, "severely changed for the worst," and Adelaide guitarist Rick Morris. The first draft was written in Sweethearts Cafe in Kings Cross, New South Wales. Walker said he "killed a couple of afternoons" putting down the lyrics, "for my own enjoyment and amusement," in the days before the band had a recording contract. "If I had imagined anybody would see those lyrics, I probably would have written them a bit differently."

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