Abstract: The paper stated the gas emission sources and emission mode of the fully mechanized top coal caving mining face, the paper analyzed the gas emissio n features of the coal wall.According to the unidirectional unsteady flow theory of the seam gas, a numerical model of the gas emission from the coal wall was establish ed and a calculation formula of the gas emission from the coal wall of the coal mining face was obtained.With the calculation results applied to No.7354 coal mining fac e in Kongzhuang Mine, the paper provided the analysis method to predict the gas emission danger of the coal wall with the average gas emission value of wall in one m ining cycle, dynamic gas emission value and max gas emission value while cutting coal in order to provide theoretical basis to the mine production layout, mine ventilati on safety management and gas prevention and control.