Ralf-Reimar Wolfram (31 March 1912 – 9 February 1945) was a Korvettenkapitän (lieutenant commander) during World War II. During his career he commanded two U-boats for a total of 118 days at sea spanning four patrols. During his third patrol he sank the SS Robert Gray, an American liberty ship. Robert Gray was a straggler from convoy HX 234 en route to Britain.

Ralf-Reimar Wolfram
Korvettenkapitän Ralf-Reimar Wolfram
Born	31 March 1912 (1912-03-31) Wilhelmshaven, Province of Hanover, Kingdom of Prussia, German Empire
Died	9 February 1945 (1945-02-10) (aged 32) U-864, Norwegian Sea
Allegiance	Nazi Germany
Service/branch	Kriegsmarine
Rank	Korvettenkapitän
Commands held	U-108 U-864
Battles/wars	World War II Action of 9 February 1945 †

For Wolfram's fourth patrol, he commanded U-864 during Operation Caesar. He was killed when U-864 was sunk by the British submarine Venturer. This was the only known instance of one submerged submarine sinking another submerged submarine. U-864 remains Wolfram's grave to this day.