Abstract: In order to improve the coal recovery rate and solve the tension problem of excavation replacement in working face, taking the mining roadway in Tunliu Coal Mine as the research object, the limit equilibrium theory and numerical simulation method was applied to analyze the distribution laws of the vertical stress in the wide coal pillar after mining upper section working face, then it studied the rational width of the narrow coal pillar in the wide coal pillar for the gob-side entry driving, and the relational width of the narrow coal pillar was determined as 5 m.