In order to ensure the safety of anti-rock burst during the stoping of filling face, take the residual strip coal pillar in filling face of Yunhe Coal Mine as the engineering background, based on the analysis of the distribution characteristics of lateral abatement pressure in adjacent goaf, an engineering mechanical model of coal pillar instability in the section coal pillar of filling face is established, the stress distribution characteristics and instability criterion of section coal pillar are studied, and the reasonable size of section coal pillar is determined. The results show that the difference in the mechanical mechanism of filling slurry and gangue leads to the unequal pressure structure of the section coal pillar in the horizontal direction; when the horizontal extrusion pressure of the section coal pillar is greater than the impedance force exerted by the roof and floor, the section coal pillar will be in danger of instability; the reasonable width of the section coal pillar was determined to be 5.1 m to 8.8 m by comprehensively considering the factors such as preventing rock burst, ensuring the reliability of filling mining and improving the recovery rate of coal resources.