Abstract: A fuel-air premixer for use in a combustor of a gas turbine includes an air inlet, a fuel inlet, a shroud, a central body and a cascade of vanes. The premixer mixes fuel and air in the annular mixing passage into a uniform mixture for injecting into a combustor reaction zone. The air from a compressor is injected into the mixer through an air inlet. The fuel is introduced into air stream via fuel injection holes that pass through the walls of the vanes which contain internal fuel flow passages. The flow field inside the premixer is broken up by the arrayed vanes into a series of small regions each containing a well designed small size mixing eddy which is steadily attached to the surface of the vanes.