More than 40 fire fighters are currently fighting the blaze which was first reported at around 5.30am at the old Comrade Club on Adelaide Street.
Police are advising that Adelaide Street is currently closed between Alfred Street and South King Street.
Neighbouring properties and adjoining buildings have been evacuated.
Fire services say that nine fire engines in addition to two Aerial Ladder Platforms from Blackpool and Preston are attending the incident.
Firefighters are using four water jets and the ALP jets to extinguish the fire.
A spokesman for the police said: "Emergency Services are currently dealing with a fire in the Adelaide Street area of Blackpool.
"We recommend residents in the neighbouring streets to keep doors and windows closed and ask you avoid the area."
Police say that nobody was in the building at the time of the fire.