Protesters also chanted slogans denouncing oil companies.
The protest was organized by a group at Cégep du Vieux-Montréal, where many students were boycotting class this week.
Police originally said the march would be allowed to proceed, but later declared it illegal, saying the protest route wasn't provided beforehand.
Officers were seen using pepper spray and tear gas as they ordered protesters to disperse. At least one person was arrested.
By about 10:30 p.m. most of the protesters had been cleared out of downtown, police said.
The march was part of two weeks of planned strikes and demonstrations, beginning last Monday, against what the students describe as the province's heavy-handed austerity measures.