PURPOSE: To provide a gas turbine combustor having a primary passage and a secondary passage for pre-mixing gaseous fuel in combustion air in which the pre-mixing of liquid fuel is carried out in at least one of these passages.

CONSTITUTION: A gas turbine cambustor 4 has combustion zones 36, 37 and concentric liners 40, 42 enclosing at least one of them. Between these liners is formed an annular passage 68 provided with an outlet communicated with the combustion zones and an inlet communicated with a portion of a compressor. There is provided a spray peg 76 for feeding gaseous fuel into an annular passage so as to mix it with the compressed air. In addition, there is provided an injection nozzle 84 for feeding liquid fuel into the annular passage through a fan-shaped channel 96 so as to be mixed with the compressed air.