Students let off flares and held up banners saying that people who had "destroyed" the university sector should not be allowed entry.
Former education minister Maria Stella Gelmini was also set to attend the event.
The protestors then tried to force a police cordon to enter the faculty where a conference on education reform was being held and scuffles ensued.
The disgruntled group threw eggs and paint at police and were blocked again when they tried to enter the building via another entrance.
Meanwhile, a handful of students inside interrupted the conference.
Fedeli responded to a heckler, saying "you come to university to study, not to attack [people]".
"I have always been open to debate...and it's not with acts of violence that you're going to advance proposals for university reform," she added.
Police have identified around 40 people who took part in the conflict.
With ANSA
