The blaze broke out at the Islamic Centre of Victoria, in the early hours of Saturday morning.
A clerk spotted the fire at 2am as smoke and flames billowed out of the building.
Firefighters arrived on scene and battled to get the fire under control for four hours.
According to reports, the centre’s Imam Shahid Hashmi was awake in the early hours of Saturday morning and checked the surveillance cameras at the mosque.
He saw that the building was on fire and realized that the alarm had been deactivated.
Mr Hashmi added: “It’s sad to stand there and watch it collapse down, the fire was so huge.”
It is not known who or what started the fire at the 17-year-old mosque.