Abstract： Geological block method was one of the most commonly used methods in the estimation of solid mineral resources reserves in China. This paper used this method to estimate the resources reserves of each coal seam in Xinsan Mine. Combined with geological characteristics of the estimation area, the parameters such as estimated area, coal seam thickness, coal seam bulk density and stratum dip angle were selected to calculate the resources reserves estimation results，and review resources reserves change conditions.The results showed that the change of block area and the increase or decrease of coal seam average thickness were the main reasons for the change of calculation results of each coal seam resource reserves.
