Three crews from Rugeley and Cannock were called to the Pied Piper pub in Pye Green Road at 10.06pm.
Firefighters dealt with 'several small fires' at the building before leaving at at around 1am. They returned at 7am on Saturday to check on the building.
An investigation is taking place into what caused the fire.
It comes after armed police were sent to the pub last month following reports of a group of people with an air rifle.
The pub has been shut since 2014. Plans were submitted to convert the building into a supermarket, but later withdrawn.
Ex-footballer Stan Collymore, who is from Cannock, gave his backing to campaign to reopen the pub two years ago.