Helmut Gröttrup (12 February 1916–5 July 1981) was a German electrical engineer. He was an assistant of Wernher von Braun in the V-2 rocket-project. Gröttrup was responsible for the radio guidance system. After the war, he worked in the Soviet rocketry program.
After World War II, Gröttrup decided to work with the Soviet rocketry program, hoping to be its leader rather than an underling of von Braun (with whom he had personality conflicts). From September 9, 1945 through October 22, 1946, Gröttrup worked under the supervision of Sergey Korolyov in the Soviet Occupation Zone. Then, all scientists and engineers working for the SU were unexpectedly moved to the USSR by train along with their families as part of Operation Osoaviakhim.
Gröttrup helped Korolev with the R-1 project, a recreation of the V-2 missile using Russian manufacturing and materials. At Kapustin Yar, he helped Korolev supervise the launching of 20 rebuilt V-2 rockets.