PURPOSE: To improve the combustion performance in the title burner by forming a throttle part in the mid-position of a fluid passage connected to an air supply source inside a cylindrical burner main body, then sucking fuel gas under a reduced static pressure depending on a high speed flow passing through the throttle part so as to eject the fuel gas mixed with the air flow.

CONSTITUTION: The burner 30 mounted in an enclosed combustion chamber of a gas turbine or the like is provided with an air introducing entrance 32 connected to the end of a supercharged air passage 3 extending from a discharge side of a blower, at one end of a cylindrical burner main body 31. The other end of the burner main body 31 is enclosed by a flange 35 having an ejection hole 34 for ejecting pre-mixture to respective combustors. A throttle part 37 is formed at a mid-position of a fluid passage 36 inside the burner main body 31. A fuel gas chamber 43 interconnected to a fuel gas chamber 43, is formed directly downstream from the throttle part 37. Then, the fuel gas is sucked by the air flow accelerated at the throttle part 37 so as to be mixed with the air flow in a mixing chamber 38.