A fuel control device and method of a gas turbine combustor, for advanced humid air turbines, in which plural combustion units comprising plural fuel nozzles for supplying fuel and plural air nozzles for supplying air for combustion are provided. A part of the plural combustion units are more excellent in flame stabilizing performance than the other combustion units. A fuel ratio, at which fuel is fed to the part of the combustion units is set on the basis of internal temperature of the humidification tower and internal pressure of the humidification tower to control a flow ratio of the fuel fed to the plural combustion units.