PURPOSE: To aim at preventing a fuel nozzle from clogging, by purging a fuel communication passage in the fuel nozzle with the use of purge air upon resting the operation of a gas turbine.

CONSTITUTION: A purge air line 15 is connected to the inlet port of a fuel nozzle 8 for a gas turbine combustor 9 in a fuel pipe line 6 through which fuel is fed from a fuel inlet 1 to the fuel nozzle 8, and a fuel shut-off valve 3 in the fuel line 6 and a solenoid valve 14 are connected together through a signal line 12. When the gas turbine stops, the fuel shut-off valve 3 is fully closed, and the solenoid valve 14 is opened in association with a signal transmitted through the signal line 12 to feed pressurized air in a fuel communication passage in the fuel nozzle 8. With this arrangement it is possible to prevent the fuel nozzle 8 from clogging.