Abstract: In order to improve the top coal recovery rate of contiguous seams and lower thick seam by simultaneous mining, based on analyzing geological conditio n of Quandian Coal Mine, the paper used PFC simulation software to analyse the parameters of top coal caving, and determined the drawing interval was 0.6 m, and u sed uplink coal caving technique. The coal caving effect was measured, and observations results showed that average caving time of every support was 84 s, the size 0 f the broken top coal was under 10 cm, the size of the broken immediate roof was under 30 cm. After top coal caving, 10. 3% of the caving mouth didnDt find gangue, a nd 86. 9% of the caving mouth controlled the proportion of gangue under 60%, average recovery rate of the working face was 80. 41%, and the highest mining rate was 84.3%.