Abstract: The harmful gases,in gob of boundary pillar working face,have the characteristics of determining the source uncomfortably and emitting with the production activities.through safety monitoring timely on harmful gases parameters,a comprehensive analysis for harmful gases sources was implemented by combining with the mine ventilation system,face recovery rate,spontaneous combustion of residual coal in gob,etc.The emission of a large number of harmful gases were effectively controlled in gob by selecting comprehensive control program of ventilation pressurized,increasing resistance and plugging,grouting isolation,etc,which ensured safe production on mining face.