To further reduce the NOX emitted from a premixing gas turbine combustor by making the flow of air flowing in the combustor uniform.

In the main body 20 of a gas turbine combustor, eight fuel burners 22 are arranged along a circumference and a pilot burner 21 is provided at the center. The air 50 from a compressor 30 flows in the main body 20 as air flows 50a, 50b, and 50c, flows to the front sections of the burners 22 through the peripheries of the burners 22, and forms a mixed gas with fuel ejected from the front ends of the burners 22 and the mixed gas is ignited by the flame coming up from the front end 21a of the pilot burner 21 and forms a flame 22a and a combustion gas 41. On the air flowing-in side of the main body 20, a straightening vane 1 is provided and fixed to the periphery of the pilot burner 21 by welding. Since many small holes are formed through the vane 1, uniform air flows are formed around the burners 22 by distributing the flowing-in air and a uniform mixed gas is formed at the front end of each burner 21. Therefor, the NOX emitted from the gas turbine combustor can be reduced further.