Due to the coupled amplification effect of “coal mining subsidence - terrain fragmentation - soil and water loss” caused by coal mining in the loess hilly and gully region of Western Inner Mongolia, the existing single remediation technologies fail to simultaneously realize geological hazard control, soil and water loss mitigation and ecological function restoration. Taking typical coal mines in the mining area of Western Inner Mongolia as research objects, this study adopts the space-air-ground integrated technology to clarify the dominant mechanism of soil and water loss aggravated by coal mining subsidence, and develops an innovative comprehensive technical system featuring zoned management, engineering remediation and biological restoration in a targeted manner. The research results indicate that surface cracks (with a maximum depth of 1.5 m) and collapse pits form preferential pathways for soil and water loss. The erosion area in regions with a slope gradient of 0°~15° accounts for 96.8%. The coupling of high erodibility of silty loam and subsided terrain is the core factor leading to the intensification of soil and water loss. The vegetation coverage increased from 43.1% in 2013 to 63.2% in 2024, while presenting obvious spatial differentiation. On this basis, three types of management units were established, including dense ground crack areas, collapse pit reconstruction areas and steep slope areas. A set of key technologies were integrated, such as ecological backfilling with coal gangue, water collection via micro-topography regulation, soil improvement with biochar, and construction of native arbor-shrub-herb communities. Remediation results show that the soil erosion modulus in the treatment area decreased from 3520 t/(km2·a) to 1180 t/(km2·a), the vegetation coverage reached 63.2%, and the soil organic matter content rose by 59.2%. This technical system breaks through three major technical bottlenecks in the mining area of Western Inner Mongolia, namely difficult solid waste disposal, topsoil scarcity and water deficiency, and provides a replicable technical model for ecological restoration of coal mining subsidence lands in arid and semi-arid loess hilly and gully regions of western China.