Abstract: Coal water slurry technology is an important branch in the development of clean coal technology in China. It is of great significance to improve the utilization efficiency of coal resources in China,reduce the pollution generated in the process of coal utilization,and realize the high value utilization of coal. It is the inevitable choice for the long-term and stable development of China's energy,which conforms to the national policy guidance and environmental protection requirements. With the expansion of coal water slurry,especially gasification slurry consumption and the improvement of energy conservation and environmental protection requirements,the quality of coal water slurry requirements are higher and higher in chemical plants. However,there are many common problems such as low concentration,poor rheological property and unsatisfactory gasification effect in gasification CWS in China,which reduce the efficiency of CWS gasifier and are not conducive to reducing cost,increasing efficiency and stabilizing production.Based on the evaluation index of CWS performance,in this paper,the measurement method of CWS performance index was introduced,and the significance of CWS concentration,viscosity,stability,flow pattern and rheology to actual production were explained.The effects of coal quality,additives,gradation and particle morphology on the performance of CWS were introduced in this paper,the direction for improving the performance of CWS was pointed out,and the significance of improving the concentration,flow pattern and fluidity of CWS with particle size gradation was emphasized.The research progress in the field of coal water slurry pulping in recent years was listed,including the compound of coal used for pulping,the research and development of new coal water slurry additives,and the introduction of the new pulping process of "breaking for grinding".The development trend of CWS technology was prospected,including the development of new pulping process and core equipment,the development of high-efficiency and economical low-order CWS additives,the treatment of chemical sludge and gasification slag and other wastes,as well as the research on the law of interaction between CWS particles and particle morphology.