U-37 may refer to one of the following German submarines:
- SM U-37, was a Type U 31 submarine launched in 1914 and that served in the First World War until sunk on 30 April 1915
- During the First World War, Germany also had these submarines with similar names:
- SM UB-37, a Type UB II submarine launched in 1915 and sunk on 14 January 1917
- SM UC-37, a Type UC II submarine launched in 1916 and surrendered in 1919
- During the First World War, Germany also had these submarines with similar names:
- German submarine U-37 (1938), a Type IX submarine that served in the Second World War until scuttled on 8 May 1945
This article includes a list of ships with the same or similar names. If an internal link for a specific ship led you here, you may wish to change the link to point directly to the intended ship article, if one exists.