The Luxembourg Palace (French: Palais du Luxembourg, pronounced [palɛ dy lyksɑ̃buʁ]) is at 15 Rue de Vaugirard in the 6th arrondissement of Paris. It was originally built (1615–1645) to the designs of the French architect Salomon de Brosse to be the royal residence of the regent Marie de' Medici, mother of King Louis XIII. After the Revolution it was refashioned (1799–1805) by Jean Chalgrin into a legislative building and subsequently greatly enlarged and remodeled (1835–1856) by Alphonse de Gisors. The palace has been the seat of the upper houses of the various French national legislatures (excepting only the unicameral National Assembly of the Second Republic) since the establishment of the Sénat conservateur during the Consulate; as such, it has been home to the Senate of the Fifth Republic since its establishment in 1958.

Immediately west of the palace on the Rue de Vaugirard is the Petit Luxembourg, now the residence of the Senate President; and slightly further west, the Musée du Luxembourg, in the former orangery. On the south side of the palace, the formal Luxembourg Garden presents a 25-hectare green parterre of gravel and lawn populated with statues and large basins of water where children sail model boats.