Knut Hagrup (né Hagerup-Svendsen; 13 November 1913 – 15 May 2003) was a Norwegian aviator.

He was born in Bergen to Henry Lie-Svendsen and Ebba Hagerup .

He served with the exiled Norwegian Armed Forces and the Royal Norwegian Air Force in the United Kingdom from 1941 to 1945, as a pilot and a technical officer.

After his retirement he was appointed professor at the Northrop University in Inglewood, California.

Among his publications are Flyet i fare from 1975, and his thesis How the aerospace-industry of western Europe will survive from 1981.