Saint-Gatien-des-Bois () is a commune in the Calvados in the Normandy region in northwestern France.
Saint-Gatien-des-Bois is located approximately 150 miles northwest of Paris, a few miles from Deauville along the English Channel, and near the port of Honfleur. The name Gatien (also rendered as Grathien) is derived from Gatianus, a bishop of Tours. In the 17th century, the settlement was a small village with a population of fewer than 500 inhabitants.
Saint-Gatien-des-Bois has an average elevation of approximately 145 metres and covers an area of 49.11 square kilometres. It is located at a latitude of 49.347ð north and a longitude of 0.187ð east. Nearby communes include Tourville-en-Auge (2.82 km), Englesqueville-en-Auge (3.36 km), Fourneville (3.67 km), Saint-Martin-aux-Chartrains (4.30 km), and Barneville-la-Bertran (4.44 km).
According to census data, the population of Saint-Gatien-des-Bois was 1,166 in 1999, increasing to 1,312 in 2006, 1,333 in 2007, and 1,359 in 2009. The population density is approximately 27.67 inhabitants per square kilometre.
In 2007, the commune had an estimated 791 dwellings, comprising 500 primary residences, 254 secondary or occasional residences, and 38 vacant dwellings.