Bouches-de-l'Elbe (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 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:

• Hamburg, cantons: Bergedorf, Hamburg, Hamm and Wilhelmsburg.
• Lübeck, cantons: Lauenburg, Lübeck, Mölln, Neuhaus, Ratzeburg, Schwarzenbek and Steinhorst (Lauenburg).
• Lüneburg, cantons: Bardowick, Buxtehude, Garlstorf, Harburg, Hittfeld, Lüneburg, Tostedt and Winsen.
• Stade, cantons: Bremervörde, Freiburg (Elbe), Himmelpforten, Horneburg, Jork, Neuhaus (Oste), Otterndorf, Ritzebüttel, Stade and Zeven.

After Napoleon was defeated in 1814, the département was redivided over the Kingdom of Hanover, the Duchy of Holstein and the free cities of Hamburg and Lübeck.