Helmut Patzig, also known as Helmut Brümmer-Patzig (26 October 1890 – 11 March 1984) was a German U-boat commander in the Kaiserliche Marine in World War I, and the Kriegsmarine in World War II.
He was captain of U-86, the vessel that sank a Canadian hospital ship, HMHS Llandovery Castle, in 1918.
Patzig evaded conviction for the war crime at the Leipzig War Crimes Trials in 1921 because he fled German jurisdiction.
During the Second World War he returned to naval service, serving as commander of the 26th U-boat Flotilla, a U-boat training group, from 1943 into 1945.