The 1979 Prix de l'Arc de Triomphe was a horse race held at Longchamp on Sunday 7 October 1979. It was the 58th running of the Prix de l'Arc de Triomphe.
The winner was Three Troikas, a three-year-old filly trained in France by Criquette Head and ridden by her brother Freddy. The filly won by three lengths from Le Marmot with the odds-on favourite Troy in third. The winning time was 2:28.9.
<span style="font-size:85%">* Abbreviations: ns = nose; shd = short-head; hd = head; snk = short neck; nk = neck</span>
Further details of the winner, Three Troikas.