Abstract: In order to successfully predict coal seam gas emission quantity on fully-mechanized large mining height working face in Zhulinshan highly gassy mine, the main mining No.3 coal seam was identified as the main research object. In allusion to the mining situation of No.3 coal seam, gas content of the No.3 coal seam was measured and the gas content in the adjacent mines was understood through laying some measurement points, the distribution regularities of gas content in the No.3 coal seam was obtained by use of separate source method, the regression method and the statistical method, and the contour map of gas content in the No.3 coal seam was drawn. The largest absolute gas emission and the maximum relative gas emission of district in the early period,the middle period and the later period of the production were gotten through predicting gas content in different production period, and it was proved that Zhulinshan Coal Mine is a highly gassy mine in different production period.