<p>A gas turbine combustor for a gas turbine power plant comprises a combustion liner connected to a turbine and provided with a main fuel nozzle assembly and a sub-fuel nozzle assembly for jetting fuel to an inside of the combustion liner through nozzle holes, a base fuel supply line, a main fuel line for supplying a fuel to the main nozzle assembly for premixing an air with the fuel jetted through the nozzle hole for carrying out a lean burning in the combustion liner, and a plurality of sub-fuel lines for supplying the fuel to the sub-fuel nozzle assembly for mixing the fuel with a combustion air for carrying out a diffusion burning in the combustion liner. The main and sub-fuel lines branch off a front end of the base fuel supply line. Distributing valves are incorporated in the main fuel line and at least one of the sub-fuel lines for distributing the fuel into the main and sub-fuel lines and degree of openings of the distributing valves are controlled by a control unit for controlling a fuel distribution ratio. The sub-fuel nozzle assembly includes a swirler provided with swirling vanes at an end portion inserted in the combustion liner for swirling the fuel therein The swirling vanes are provided with a combustion air passage to which the nozzle holes of the sub-fuel nozzle assembly are opened.</p>
