The move against GOP congresswoman Elise Stefanik came in the wake of the Trump riot and after she was among 147 House Republicans to vote against certifying Joe Biden’s victory.
The prestigious university initially asked Ms Stefanik to stand down from its senior advisory committee but when she declined they removed the pro-Trump New York politician.
"Elise has made public assertions about voter fraud in November’s presidential election that have no basis in evidence, and she has made public statements about court actions related to the election that are incorrect," said Harvard Kennedy School Dean Douglas Elmendorf.
"Moreover, these assertions and statements do not reflect policy disagreements but bear on the foundations of the electoral process through which this country’s leaders are chosen.”
Ms Stefanik, a 2006 graduate from the university, called the action “a rite of passage and badge of honour.”
“The decision by Harvard's administration to cower and cave to the woke Left will continue to erode diversity of thought,” she said in a statement.
“The Ivory Tower's march toward a monoculture of like-minded, intolerant liberal views demonstrates the sneering disdain for everyday Americans and will instill a culture of fear for students.”
It is the latest move in a backlash against lawmakers who voted not to certify the electoral college results following the 6 January violence, which left five dead including a US Capitol Police officer.
A string of major corporations have announced they will no longer make financial contributions to those lawmakers who opposed Joe Biden’s win.