Bouches-de-l'Elbe (German: Elbmündungen) is the name of a département of the First French Empire in present Germany that survived three years. It is named after the mouth of the river Elbe. It was formed in 1811, when the region, originally belonging partially to Bremen-Verden (which in 1807 had been intermittently incorporated into the Kingdom of Westphalia), to Hamburg, Lübeck and Saxe-Lauenburg, was annexed by France. Its territory is part of the present German lands Lower Saxony, Schleswig-Holstein and Hamburg. Its capital was Hamburg. The département was subdivided into the following arrondissements and cantons (situation in 1812):
- Hamburg, cantons: Hamburg, Bergedorf, Hamm and Wilhelmsburg.
- Lübeck, cantons: Lübeck (2 cantons), Lauenburg, Mölln, Neuhaus (Elbe), Ratzeburg, Schwarzenbek and Steinhorst.
- Lüneburg, cantons: Lüneburg, Bardowick, Buxtehude, Garlstorf, Harburg, Hittfeld, Tostedt and Winsen upon Luhe.
- Stade, cantons: Stade, Bremervörde, Freiburg (Elbe), Himmelpforten, Horneburg, Neuhaus (Oste), Otterndorf, Ritzebüttel, Jork and Zeven.
Its population in 1812 was 375,976.