The Labour-backing Hawking told The Times, "I regard Corbyn as a disaster. His heart is in the right place and many of his policy are sound but he has allowed himself to be portrayed as a left wing extremist. I think he should step down for the sake of the party."
The 75-year-old professor, who was diagnosed with motor neurone disease in 1963 but went on to become one of the worlds most famous scientists comment came as shadow chancellor John Mcdonnell tried to heal divisions within the party amid claims that a soft coup was underway.
It won a concurrent by-election in Stoke with a reduced majority.