To provide a combustion device for a gas turbine in which the size of a catalytic combustion device for burning exhaust gas of an anode for the gas turbine can be extremely reduced and a stable combustion can be achieved in a simple structure.

The combustion device for the gas turbine comprises a cathode exhaust gas line 22 for supplying cathode exhaust gas 7c including oxygen to a gas turbine power generator 16, the catalytic combustion device 25a for burning the low calorie exhaust gas 4a of the anode by compressed air 26b to supply combustion exhaust gas 11a to the cathode exhaust gas line and a burner combustion device 25b for burning high calorie fuel gas 1a by compressed air 26a to supply combustion exhaust gas 11b to the cathode exhaust line.