文中根据在北票煤田开采上保护层时实测的结果,探讨了保护层开采后,被保护层中瓦斯活动,岩压活动及煤质等方面的数量变化关系.分析了保护作用的机理及有效范围.讨论了层间岩性,煤层倾角,开采深度,开采时间等因素对保护效果的影响,并提出了北票煤田使用保护层开采时的有关参数. Based on the measured results of the protective layer in Beipiao coalfield, the paper discussed the relationship between the quantity change of gas activity, rock-pressure activity and coal quality in the protected area after the exploitation of the protective layer.The mechanism of the protective effect was analyzed The influence of interlaminar lithology, coal seam inclination angle, mining depth, mining time and other factors on the protection effect are discussed, and the relevant parameters when using protective layer in Beipiao Coalfield are discussed.