Summers, whose brusque management style has won both praise and contempt, sparked controversy last year when he said innate differences between men and women may help explain why so few women work in the academic sciences.
He has since apologized repeatedly for his remarks.
But the abrupt resignation of the arts and sciences dean William Kirby, on January 27 deepened opposition against him. Several faculty have accused Summers of pushing Kirby out and called for his resignation at a faculty meeting this month.
"The university has been in a state of paralysis. I've never seen anything like this before," Farish A. Jenkins Jr., a Harvard zoology professor, told Reuters.
"Harvard can't be run by one man. It is a collaborative enterprise with many fine people," said Jenkins, one of a dozen professors who confronted Summers at a faculty meeting this month and suggested that he step down or be fired.
Following an expected yearlong sabbatical, Summers will return to Harvard as a professor in economics, public policy, and international affairs, the university said.
What, he isn't going to be a professor of evolutionary biology? But he claims to know so much about women's biological natures!