The Prix Guillaume d'Ornano is a Group 2 flat horse race in France open to three-year-old thoroughbreds.

It is run at Deauville over a distance of 2,000 metres (about 1¼ miles), and it is scheduled to take place each year in August.

The event was established in 1952, and it was originally called the Prix de la Côte Normande.

The present system of race grading was introduced in 1971, and for a period the Prix de la Côte Normande was classed at Group 3 level.

It was named in memory of Guillaume d'Ornano, a former owner of Haras de Manneville, a stud farm near Deauville.