Taking the production geological conditions of 3-1 coal seam in Nanliang Coal Mine as the engineering background, the broken structure of the basic top rock beam above the coal pillar after the mining face and the pressure distribution law when the coal pillar is left in different sizes was studied, the stability of the coal pillar was analyzed , and the optimal width of the coal pillar was obtained. The results showed that when the width of the coal pillar was optimized from 15m to 9m, there was no obvious deformation of the coal pillar and its overlying strata, and the stability was good. When the coal pillar width was 8m, the coal pillar was not enough to support the overlying rock load and was crushed, and the roof structure changed obviously. The stress distribution of coal pillar changed from "double hump" to "single hump". Field monitoring results showed that the stability of surrounding rock after coal pillar optimization had no obvious change compared with that before optimization, and the stability was good.
