In order to study the control theory and technology of large-section cut-out of the lower coal seam, the 2901 cut-eye of Tiexin Mine was selected as the research object. The theoretical analysis and numerical analysis were used to determine that the 2901 cut-eye should be staggered more than 15 m, and the principal stress was reduced. The simulation showed the extension trend of the surrounding rock pulling and shearing plastic zone during the process of cutting eye width was from 3.5 to 7 m. It was believed that the key part of this type of eye-cutting support was the roof plate, and the shoulder-stable stability zone was used as the anchoring foundation for strengthening the support to ensure the stability of the surrounding rock. The technical parameters of the truss anchor cable and bolt joint support were determined. The results showed that the large-section cut-out could achieve self-stability after 7 d, and no obvious mine pressure appeared, which provided a reference for large-section cut-eye support under similar conditions.