Fire crews are battling a four-alarm roofing fire at the Jones Avenue Adult Centre in Greektown.
Firefighters were called to 540 Jones Avenue just before 5 p.m.
Seven roofers were apparently on top of the building when the flames broke out, but they were able to get out safely.
Toronto Fire are cutting off pieces of the roof in order to gain access to the fire and it has reportedly spread into the building. They are also using aerial ladder operations.
The school has been evacuated and no injuries have been reported.
There are also reports of propane and gas cylinders on the roof.
The school is an English as a Second Language learning centre for adults.