Abstract: The emission of coal water slurry gasification slag is in large quantity in China, how to use it reasonably in agricultural activities is significant to improve the comprehensive utilization of coal water slurry gasification slag. In this study, field experiments were conducted to investigate the effects of coal water slurry gasification slag and Jerusalem artichoke on improving sandy soil. The results showed that: The soil water content of 0-20 cm depth increased by 2.09% compared with the initial value, and the total salt content decreased by 9.5%. The contents of available potassium, alkali-hydrolyzable nitrogen, total nitrogen, available phosphorus and organic matter in soil were increased by 31.91%, 254.2%, 108.00%, 52.74% and 3988.4%, respectively, compared with the soil without coal water slurry gasification slag. After the application of gasification slag, the soil water content in the surface layer (0-20 cm depth) was increased significantly, but there was no significant change in the depth of 20 - 50 cm; After planting Jerusalem artichoke, the contents of soil available potassium, total nitrogen, available phosphorus and organic matter were increased by 26.19%, 440%, 29.8% and 416%, respectively. While soil pH and total salt content were decreased by 6.38% and 27.8%, respectively. When the application of coal water slurry gasification slag with Jerusalem artichoke, soil pH value, soil total nitrogen and available phosphorus were increased by 8.65%, 211.86% and 64%, respectively, while total salt content and alkali-hydrolyzable nitrogen were decreased by 13.04% and 83.90%, respectively; In the growth period of Jerusalem artichoke, the plant height, root depth, stem diameter, aboveground biomass and yield of the experimental group were increased by 18.56%, 26.77%, 3.54%, 12.57% and 6.21% compared to control, respectively. These results were suggested that there were certain effects on the improvement of water content and soil fertility in sandy soil by applying coal water slurry gasification slag and planting Jerusalem artichoke. At the same time, the application of coal water slurry gasification slag could obviously promote the growth of Jerusalem artichoke.