Born in Charolles, Saône-et-Loire, Roux moved to Paris with his family after the war, where they set up a charcuterie (delicatessen). At the age of fourteen he became a patissier (pastry chef), and later followed his elder brother Albert back to Paris to work as a chef.

When Albert moved to London, Michel again followed him, and in 1967 they opened their first restaurant, Le Gavroche, which became the first restaurant in Britain to gain one, two and then three Michelin stars. In 1972 they opened the Waterside Inn in Bray, Berkshire.

Michel was awarded the Meilleur Ouvrier de France for patisserie in 1976 and an honorary OBE alongside his brother in 2002 and is the recipient of The International Center in New York's Award of Excellence.

In a poll of UK chefs carried out by Caterer and Hotelkeeper magazine in 2003, Michel and his brother Albert were voted the most influential chefs in the country. Michel Roux's son, Alain Roux, currently runs the Waterside Inn in Bray.

In July 2008, Roux announced that he would move permanently to Crans-Montana, Switzerland, citing concerns about the state of public safety in Britain.