Abstract: In this paper, the method of numerical calculation is used to study the distribution of the original stress field and displacement field before the excavation. In the meanwhile, we revealed the influence of the narrow coal pillar width on the stress field and displacement field in the residual pillar. The results show that the peak value of the vertical and horizontal stress will transfer to the deep of the coal mass, the influence range of the vertical and horizontal displacement will increase, and the stable region of the residual pillar will decrease with the increase of the narrow coal pillar. In addition, the narrow coal pillar will be more stable when the width reaches 6 meters with elastic core region.