Abstract: The caving laws and dynamic evolution laws on space structure of stope overlying strata are researched by taking the large inclined coal seam with dip mining stope as the research object and the method of similar material simulation and theoretical analysis, and the overlying strata space structure mechanical model is established. The results show that the roof weighting interval is longer by adopting dip mining and the first weighting interval of basic roof is 50 m while the periodic weighting interval is 25 m. Besides, the space structure of stope overlying strata is evolving constantly, and several basic rock beams structure at different horizons as well as an asymmetric crack arch structure which crosses the whole stope will be formed finally. However, the original lower basic rock beams at the middle and upper parts of stope will translate into caving zone and the basic rock beams will extend to the upper strata along the tendency with the shape of stair-step. The phenomenon of coal wall caving and the roof-falling in front of supports will generate easily at the lower area of stope despite the arch springing bearing position is lower and the bound level is higher. Therefore, the stability control of support-surrounding rock system should be strengthened.