In a statement Prof Richardson said: “UEA and the whole Higher Education sector are now facing a variety of further challenges but genuine opportunity also lies ahead for UEA.”
The professor of microbial biochemistry, who has been at the university for 32 years, said the UEA could now “develop a new long-term vision to take it forward”.
He will become an emeritus professor of UEA, the university said.
Dr Sally Howes, chair of UEA council, said it was “a sad day for the university”.
Provost, and deputy vice chancellor, Prof Christine Bovis-Cnossen will be acting vice chancellor whilst the university begins its search for a permanent replacement.