Abstract: Due to the particularity of mechanized caving mining, the gas emission intensity of mechanized caving mining face increased significantly, which resulted that the adaptability of value range decreased for calculation formulas and prediction parameters of some "sources" in "separate source method", and the prediction accuracy reduced. In order to increase the adaptability of "separate source method", the gas data of caving mining face in Yangquan No.5 Coal Mine was summarized, and the effect parameters of gas emission prediction in the adjacent layer were analyzed. The gas emission prediction method suitable for the adjacent layer in caving mining face was proposed, and it achieved satisfactory fitting results.