Abstract: To investigate the ecological and environment effects of land-use changes under different mining modes, this study utilized the Google Earth Engine (GEE) cloud computing platform to construct a remote sensing ecological index (RSEI) by integrating the greenness, heat, dryness, and wetness indicators. The RSEI was utilized to assess the ecological quality of two mining areas with different mining modes: the Guqiao Coal Mine in Huainan City (underground mining) and the Nanshan Iron Mine in Ma’anshan City (open-pit mining). Through a comparative analysis of relevant data from 2000 to 2020, this study analyzed the dynamic evolutionary patterns between land use changes and ecological quality in the two mining areas. The results indicate that cultivated land occupied the largest proportion in both mining areas. The underground mining area was characterized by a significantly expanded water area, whereas the open-pit mining area featured reduced cultivated and forest lands and increased construction land. Both mining areas exhibited overall good-to-fair ecological quality. Specifically, the RSEI values for the Guqiao Coal Mine were 0.60, 0.82, 0.71, 0.65, and 0.68, while those for the Nanshan Iron Mine were 0.58, 0.59, 0.59, 0.63, and 0.64. Among various land use types, construction land and water bodies displayed relatively poor ecological conditions, whereas forest and cultivated lands exhibited more favorable conditions. The underground mining area showed surface subsidence and the transition of cultivated land to water areas, leading to deteriorating ecological quality. In contrast, the open-pit mining area showed soil stripping, shrinking forest and cultivated lands, and construction land expansion, contributing significantly to the declining ecological quality.