Abstract: Residual coal pillars exist in the Jurassic goaf above the extra-thick Carboniferous coal seam of Tongxin Coal Mine, with a vertical interval of about 180 m between the two seam groups. The concentrated stress of the residual pillars transmits downward along the hard roof strata, inducing strong mining pressure manifestations, such as large-scale rib spalling of the coal wall, support overload and severe roadway deformation, in the distant lower Carboniferous isolated working face. To address the strong mining pressure problem beneath the Jurassic coal pillars, taking the 8102 isolated working face as the engineering background, theoretical analysis, mechanical calculation and FLAC^3D numerical simulation were adopted to reveal the mechanism of strong mining pressure induced by the load transfer of the Jurassic coal pillars: the large mining-induced space of the extra-thick Carboniferous seam leads to the collapse of the high-level hard roof and the joint destabilization of the middle- and low-level roofs, and the concentrated stress of the coal pillars is then continuously transmitted downward through the floor, which is the main cause of the strong mining pressure. Based on theoretical calculation of the caving zone height and field measurement, the fracturing horizons were determined, and a far-near field collaborative hard roof control technology for the long-interval dual-system coal seams was established, combining surface high-level hydraulic fracturing with underground low-level hydraulic fracturing. Surface directional drilling with a three-stage casing structure and hydraulic sand blasting staged fracturing were applied to weaken three layers of thick hard sandstone, and the induced fractures basically covered the entire working face. The control effect was verified by microseismic monitoring and support resistance measurement and compared with the 8101 working face without treatment. The results show that the energy released by the effective microseismic events decreases from 3.54×10⁷ J to 6.92×10⁵ J, i.e., a reduction of 2 orders of magnitude; when the working face passes through the Jurassic coal pillar, the dynamic load coefficient increases by 0.07, the proportion of the high resistance interval of the supports increases by 7.3%, and the support overload rate decreases from 5.0% to 0, indicating a sufficient support capacity. The research results can provide engineering references for the prevention and control of strong mining pressure in isolated working faces beneath coal pillars of dual-system coal seams.