German submarine U-108

U-108 may refer to one of the following German submarines:


 * SMU U-108, a Type Mittel U submarine launched in 1917 that served in the First World War, and surrendered in 1918; became French submarine [[French submarine Léon Mignot|''Léon Mignot}}
 * During the First World War, Germany also had this submarine with a similar name:
 * SMU UB-108, a Type UB III submarine launched in 1917 and sunk in 1918


 * GS U-108 (1940), a Type IXB submarine that served in the Second World War and was sunk in 1944