Part of a road in St Peter Port has been closed due to a cable fault.
Guernsey Police were called to the Prince of Wales pub in Smith Street at 10.40pm.
The building had lost power and people said they could smell burning.
The pub and beer garden were evacuated while police cordoned off the area.
Guernsey Electricity were called in to attend the fault.
The pub's electrical power resumed at 4.15am.
The top of Smith Street is still cordoned off due to a hole in the road where repairs are taking place.