Dorval's Queen of Angels Academy, an institution for more than a century, will be closing its doors at the end of the current school year.
The board of directors sent a letter to its alumni Thursday evening informing them of the closure, saying the school can't afford to go on.
They say it's due to a high deficit, rising costs and low enrolment. It says the number of students enrolled has gone from 515 students a year to 186.
"I really hope that we at least have the chance to say goodbye to the school, the teachers, the memories, if I can take a chunk of the building with me, I will," Abigail Jacobs who graduated in 2007 said.
"My younger daughter found it was a little buttoned down for her, and she wanted to go to school with boys, so she is finishing her high school at another school," Steve Traynor, a parent who enrolled two daughters at QAA told CJAD.
In its letter, the school said it considered co-education, adding a French stream and merging with other private schools to stay open.
It said it was forced to double their fees over the last seven years to stay open and they would have to double them again next year to stay open.
The Queen of Angels Academy refused to comment.