Abstract: To study the stability of roadway support under different top cutting heights and improve the safety and efficiency of underground support operations, this article takes a coal mine in Shaanxi as the analysis object, and uses discrete element simulation and distributed real-time monitoring methods to analyze the changes in the roof from collapse to stability at different measuring points. The scientific top cutting height of the coal mine underground working face was obtained, and finally field experiments were conducted to verify the research content. The results show that adopting the top cutting scheme can eliminate the damage of the basic roof cantilever beam to the retained roadway structure, effectively improve the stability of the surrounding rock of the roadway. At a reasonable top cutting height, the convergence of the roof and floor is reduced by 68% compared to the situation without top cutting, and the amount of coal wall spalling is reduced by 59%, significantly improving the stability of the surrounding rock of the underground roadway in coal mines.