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针对沿空留巷围岩要经受上下两个区段工作面采动应力影响，围岩变形量大、巷道维护困难的特点，以沁新煤矿为工程背景，运用数值计算的方法得出了沿空留巷全寿命期围岩应力演化规律和变形特征。通过对围岩加、卸载荷规律及破坏效应的分析，总结了沿空留巷围岩产生大变形的原因。结果表明：①巷旁支护体与实体煤帮力学性能的差异及其在形成稳定承载结构过程中为适应上区段工作面顶板垮落而产生的围岩持续变形是沿空留巷围岩大变形的主要组成部分；②沿空留巷全寿命期内围岩的受力可看作卸围压条件下的三次轴向加载和卸载作用，卸围压条件下的反复加卸载在加剧围岩变形破坏的同时也是围岩变形量积累的过程，最终导致围岩大变形的发生。“,”Aiming at the serious deformation of surrounding rock in gob‐side retaining due to the redistribution of stress caused by two working face during its service period ,the deformation characteristics of the surrounding and the stress evolution law were investigated by finite analysis based on the case study conducted in Qinxin mine .The reasons for the large deformation of surrounding rock were summarized based on the damage effect of rock by loading and unloading cycles .Combined with this research ,two conclusions have been drawn as following :① in order to adapt to the roof collapse of the first working face and form a stable bearing structure , the continuous deformation of surrounding rock caused by the difference of mechanical properties between roadside support and integrated coal beside roadway was the main component of the large deformation of gob side entry retaining surrounding rock ;② the surrounding rock experienced three times loading and unloading cycles in axial direction for gob‐side entry retaining in whole service period .Deformation and destruction of surrounding rock were intensified as consecutive loading‐unloading cycles under unloading confining pressure , and which was also a process of accumulation of surrounding rock deformation . This was the key reason that caused the large deformation of gob‐side entry retaining surrounding rock as well .