Abstract: Cascade utilization is one of the important methods for coal´s efficient and clean utilization. Semi-coke，a byproduct made from low-rank coal in pyrolysis，accounts for about 50% to 70% mass of raw coal and contains about 80% of the energy in raw coal. Thus，the clean and efficient utilization of semi-coke is a key to the cascade utilization of coal. Summarizing the current problems of semi-coke applied in China´s industries，the necessity to realize cascade utilization of low-rank coal by large-scale and clean combustion of semi-coke was analyzed，and the research progress on existed clean and efficient combustion technology of semi-coke was concluded.It provide a reference for future research in this field.

Key words: pyrolyzed semi-coke, utilization methods, clean and efficient, co-combustion, clean fuel