Abstract: In order to study the effect of inorganic mineral of long flame coal to coal dust wettability,based on long flame coal samples from Erdos Shangwan Mine,She nmu Halagou Mine,Xinjiang Tacheng Sergio Coal Mine as study object,coal ash content measurement,wet contact angle test and X- ray diffraction scanning test were cond ucted. With the application of MDI Jade6.5 software,from a view point of qualitative and quantitative,inorganic mineral features of coal sample ash were analyzed and the f eatures were applied to study on coal dust wettability. With data fitted,the relationship between coal dust wettability and inorganic mineral was established. The results sho wed that ash of long flame coal from different regions would mainly be primary mineral quartz as well as the secondary mineral kaolinite and hematite,hydrophilicity capacit y of coal dust would be increased with increased ash yield of coal. Rietveld quantitative analysis showed that quartz content was about 70%,kaolinite and hematite would b e significant varied with coal sample varied. Therefore quartz existed in ash was selected as the standard to evaluate coal dust hydrophilicity capacity. The quartz content a nd wet contact angle would be in quadratic function relationship and could provide quantitative index to study on the coal wet capacity.