Born at Dessau in Germany, von Ohain took his PhD in aerodynamics at Göttingen in 1935. He immediately joined the Heinkel Aircraft Company at Rostock. It had long been apparent to engineers that if planes were to fly faster they would have to fly higher and so benefit from the lower air resistance. But in a thinner atmosphere propellers and piston engines worked badly. The dilemma, von Ohain realized, could be resolved if turbojets were used. Thus in 1935, four years after Frank Whittle, von Ohain took out his first patent on the gas-turbine jet engine.

Backed by Ernst Heinkel (1885–1958) he began to work on the He 178. In September 1937 a hydrogen-fueled bench model produced a 250-kilogram thrust. The plane was ready for its test flight, the first jet flight ever, in August 1939 just before the outbreak of World War II, when it reached a top speed of about 350 miles per hour. Whittle's first jet, the Gloster E28/39 prototype, had its maiden flight in 1941.

Heinkel went on to develop the He 280 powered by two von Ohain engines. By this time, however, Heinkel had lost the confidence of the Nazis and the contract to develop a jet fighter was awarded to Messerschmitt. The Me 262, powered by Junkers-built jet engines, entered service in late 1944 with a top speed of 550 mph. Although 1,430 were built, only about 400 actually saw combat and they arrived too late to influence the war's outcome.

Despite this von Ohain found himself in great demand when peace came and in 1947 he began work for the U.S. airforce on the design of a new generation of military jets at the Wright-Patterson base, where he remained until 1975. After a further spell as chief scientist at the Aero-Propulsion Laboratory, von Ohain retired in 1979.

In 1991 he shared with Whittle the Draper Prize – the engineering equivalent of the Nobel Prize – for their independent invention of the jet engine.