Saint-Jean-de-Monts () is a commune in the Vendée department in the Pays de la Loire region in western France.
The town is situated in the west of the département, between Notre-Dame-de-Monts and Saint-Hilaire-de-Riez. It is split in two by a long plantation of pine trees, stretching from north to south along the coast. The centre-ville lies to the east of the cordon, while the seafront forms a center to the west.
Saint-Jean-de-Monts is known for its sandy beach, which is more than eight kilometres long. Due to its often low tides, it offers a great area for walkers, fishermen, and beach games.
The town is noteworthy for the recent restoration of its seafront, a town planning operation that took over five years to complete. The result now means a network of footpaths and cycle tracks are enhanced by plants, flowers and shrubs.
The predominantly flat terrain has allowed for the development of a vast 500 km<sup>2</sup> network of cyclepaths, known as the Sentiers Cyclables de la Vendée. These paths stretch from the island of Noirmoutier in the north, south past Saint-Gilles-Croix-de-Vie.
Saint-Jean-de-Monts has an oceanic climate (Köppen climate classification Cfb) closely bordering on a warm-summer Mediterranean climate (Csb). The average annual temperature in Saint-Jean-de-Monts is . The average annual rainfall is with November as the wettest month. The temperatures are highest on average in July, at around , and lowest in January, at around . The highest temperature ever recorded in Saint-Jean-de-Monts was on 27 June 2019; the coldest temperature ever recorded was on 16 January 1985.
Since 1867, bathers have been coming to the beach at Saint-Jean-de-Monts in large numbers, and since 1892 it has been the inspiration for many artists. The original church still lies in the center of the old village.