Saint-Cézaire-sur-Siagne (French pronunciation: [sɛ̃ sezɛʁ syʁ sjaɲ], literally Saint-Cézaire on Siagne; Occitan: Sant Cesari de Sianha) is a commune in the Alpes-Maritimes department in southeastern France.

Far from the major thoroughfares, Saint-Cézaire-sur-Siagne lies halfway between the beaches of the Côte d'Azur and the ski resorts of the Maritime Alps.

It is located on a plateau at 475 m. Protected from north winds by the alpine foothills around Grasse, it enjoys an exceptionally tempered climate.

Saint-Cézaire-sur-Siagne is located in the western part of Alpes-Maritimes, perched on a spur that dominates the valley of the Siagne.

On the southwest are the valley of the Siagne and the massif of Tanneron, which forms the boundary between Alpes-Maritimes and the department of Var.