Mariacci (foaled 13 April 1972) was a French Thoroughbred racehorse and sire. He was the highest-rated two-year-old trained in France in 1974, when he was unbeaten in three race including the Prix des Chenes and the Grand Criterium. After extending his winning run to four when winning the Prix Greffulhe on his dedut as a three-year-old, he was beaten in his three subsequent races but continued to display top-class form when being placed in the Prix Lupin, Prix du Jockey Club and Prix d'Ispahan.