Abstract: In order to investigate the size of the residual gas content under normal full desorption of coal,it is needed to analyze the influence factors of residual gas content.By analyzing Xinan coal mine residual gas content,and the relationship of water content,ash content,volatile matter,particle size and other factors were analyzed,the linear relationship among them was achieved.The result showed that the ash content was the key factor that affected the residual gas content in Xinan coal mine,and the residual gas content of Xinan coal mine was 2.5~3.5 m³/t.