Gironde is the largest department in the Nouvelle-nouvelle-aquitaine/gironde region of Southwestern France. Named after the Gironde estuary, a major waterway, its prefecture is Bordeaux. In 2016, it had a population of 1,566,679. The famous Bordeaux wine region is in Gironde. It has six arrondissements, making it one of the departments with the most arrondissements (Nord also has six, while Pas-de-Calais has the most of any department, with seven).

Gironde is one of the original 83 departments created during the French Revolution on 4 March 1790. It was created from parts of the former provinces of Guyenne and Gascony.

From 1793 to 1795, the department's name was changed to Bec-d'Ambès to avoid the association with the Girondist political party of the French

. Gironde is well known for the Côte d'Argent beach which is Europe's longest, attracting many surfers to Lacanau each year. It is also the birthplace of Jacques-Yves Cousteau who studied the sea and all forms of life in water.

The Great Dune of Pyla in Arcachon Bay near Bordeaux is the tallest sand dune in Europe.