The union representing faculty at St. Clair, Lambton and 22 other colleges has set a strike deadline of next Monday.
The Ontario Public Service Employees Union says it took the step after the College Employer Council walked away from the bargaining table.
"Obviously, our members would like to be in a classroom with the students, but unfortunately, we have to support our position, and we have to take the necessary action to do so," said Bernie Nawrocki, head of Local 138 at St. Clair College in Windsor.
The employer council denies it walked away from the table.
It says OPSEU announced the strike action after it rejected the colleges' final offer.