Abstract: To reveal the mechanism of rock burst in face-reduced isolated coal body under horst cutting conditions, taking the determination of the reasonable face-reduced position of face-reduced isolated coal body under horst cutting conditions in the 7302 working face of Zhaolou Coal Mine as the engineering background, this study adopted research methods including field measurement, numerical simulation and theoretical analysis to investigate the rock burst mechanism of high-stress isolated coal body in deep well horst structures, determine the reasonable dip length of isolated coal body, and propose targeted prevention and control technologies. The results show that: the horst structure, dip length of face-reduced isolated coal body, and working face advance distance are the dominant factors affecting the stress concentration degree of face-reduced isolated coal body, among them, the influence of horst structure on the stress concentration of face-reduced isolated coal body decreases gradually from near to far, and the dip length of face-reduced isolated coal body is negatively correlated with its stress concentration degree, while the working face advance distance is positively correlated with the stress concentration degree of face-reduced isolated coal body. Based on a quantitative method for the bearing stress of face-reduced isolated coal body under horst cutting conditions, the bearing stress of face-reduced isolated coal body under different conditions was visually presented, and the engineering criterion for the instability of face-reduced isolated coal body was derived, and the rock burst mechanism of high-stress isolated coal body in deep well horst structure areas was revealed: with the decrease of the dip length of isolated coal body, the superimposed peak area of transferred stress and self-weight stress enters the influence range of tectonic stress, resulting in a continuous increase in the total superimposed stress, when the total stress increases to the bearing limit of coal body, overall instability-type rock burst occurs. In summary, targeted rock burst prevention and control technologies for face-reduced isolated coal body in horst structures were propesed, and the dip length of face-reduced isolated coal body under horst cutting conditions was determined to be 110 m, which ensured the safe mining of the 7302 working face.