Abstract: This paper focused on the roof stratum fracture evolution and surrounding rock stress in coal mining. Using CDEM simulation, theoretical analysis, and engineering validation, the applicability of abrasive water jet cutting technology in gob−side entry retaining of coal mines was systematically investigated. A mechanical model of the end−suspended roof was established, and the roof fracture process under three rock−beam structures was simulated. The composite roof fracture and the surrounding rock mechanical behavior were further analyzed under different cutting−slot lengths. Finally, the application effect of technology design parameters was verified through engineering practice of gob−side entry retaining in a coal mine. The research shows that the cantilever roof structure conforms to the cantilever beam mechanical theory, with roof fracture initiating at the rock beam top and extending toward the bottom until penetration leads to instability and collapse; the integral suspended roof structure fractures from the top to bottom, with the fracture penetration surface first forming in the goaf behind of mining face and then extending toward the advancing direction; the composite suspended roof structure in the end area exhibits layered fracture characteristics, following a bottom−up progressive failure pattern; increasing the roof cutting slot length enhances the connectivity of rock fracture and alleviates the roadway deformation. Engineering practice confirms that by adopting abrasive water jet roof cutting parameters including a 15°borehole angle, 75 mm diameter, 1 m hole spacing, 70 MPa jet pressure, 1.5 kg/min abrasive supply rate, and 250 mm/min nozzle traverse speed, effective unilateral cutting depths of 100~200 mm can be achieved, and the controlled roof fracture and surrounding rock stability are consistent with simulation results. These research findings provide valuable guidance for the safe and efficient mining of coal seams under hard roof conditions.