A cyclone combustor of the present invention uses a novel pre-mixture injection scheme to optimize performance. The cyclone combustor includes a cylindrical combustor can and three fuel/air premixing tubes entering the combustor can radially, with a tangential offset. The tangential offset is designed to provide an optimized circulation in the combustor can for improvement of liner life span, flame stability and engine turn-down. The ignition and pilot fuel systems are placed to take advantage of the premixing tube entry locations and the tangential direction of the mixture flow momentum in the combustor can. The special combination of the parallel axes of the combustor can and the mixing tubes provides a right angle between an outlet section and the major tube section of each premixing tube. The cyclone combustor of the present invention can meet the requirements for low NOx and CO emissions.