Crews from Halifax, Illingworth and Rastrick were called to the club on Waterhouse Street at 8.55pm today.
Three fire engines are in attendance and crews are using five breathing apparatus and a large jet to extinguish the fire.
At 9.48pm the club was still on fire, but firefighters appeared to have the flames under control.
It is not believed that the club was open at the time of the fire and there are no reported injuries.
A spokesperson for West Yorkshire Fire said: "Three fire engines are in attendance at the Acapulco nightclub in Halifax.
"They are using five breathing apparatus, a large jet and a positive pressure ventilation fan.
"There are no reports of injuries and the extent of damage is not yet known.
"The cause of the fire is unknown but it appears to have started from the roof of the club."