This paper reviews and analyses the major findings of research during the last 15 years in Harbin Institute of Technology, on bias coal combustion technologies. Five problems in China's coal combustion in boilers of power plant are given. The theory and characteristics of air-surrounding-fuel flow of bias coal combustion technologies are introduced and analysed. Industrial experiments tested the theory of airsurrounding-fuel .To greatly decrease the NO_x emission, the paper points out the development of these technologies in the future.