Demonstrators are holding a national day of action in support of Palestine at about a dozen universities around the nation on Wednesday.
The protests come amid an escalation in violence after Israel resumed air and ground operations against Hamas militants on March 18, ending a two-month ceasefire.
"We want better universities. We want universities for public good and for social good," Sydney University Staff for Palestine and academic Markela Panegyres said.
Protesters will push back against a new working definition of anti-Semitism adopted by 39 tertiary institutions.Â
It defines the term as "discrimination, prejudice, harassment, exclusion, vilification, intimidation or violence that impedes Jews' ability to participate as equals in educational, political, religious, cultural, economic or social life".
"Criticism of the policies and practices of the Israeli government or state is not in and of itself anti-Semitic," the definition says.
But it says that criticism can be anti-Semitic when it is grounded in harmful stereotypes and when it calls for the elimination of the State of Israel or all Jews.
Ms Panegyres said the new definition is "a big attack on freedom of speech" because its vagueness can be "weaponised" and "leaves it up to interpretation by people acting in bad faith".
"It has a chilling effect on staff and students. It's fostering a climate of fear where students and staff are concerned with disciplinary action for speaking out," she told AAP.
Several students and staff at the University of Sydney have already faced disciplinary action, with some threatened with suspension and staff told to change course materials, she said.
The rally follows prolonged student encampments on campuses in 2024, but Ms Panegyres says the "repressive" nature of how universities are being run meant that fewer people are coming out to mobilise.
"We're actually hoping that this national action tomorrow can be a revival of that spirit," she said.
Israel launched its offensive in Gaza, which has killed more than 50,000 Palestinians, after Hamas fighters stormed an Israeli music festival on October 7, 2023, killing 1200 people and taking hundreds hostage.