<p>Under the transition from open-pit to underground mining, slopes above underground goafs commonly exhibit asymmetric subsidence and downslope deformation, posing increasing challenges for engineering assessment. To address the lack of simplified analytical methods for such conditions, this study develops a slope-subsidence prediction framework by extending classical flat-ground settlement-trough theory to slope environments. The proposed method comprises three coupled steps: construction of an equivalent horizontal settlement trough, introduction of a terrain-induced biased-loading correction, and geometric mapping of the corrected response back onto the actual slope surface. A Python-based computational model was developed to investigate the effects of internal friction angle, Poisson’s ratio, unit weight, elastic modulus, slope angle, and burial depth on the magnitude and morphology of slope subsidence, and gray relational analysis was employed to identify the dominant controlling factors. The Fushun West Open-Pit Mine was selected as the primary engineering case, whereas the Pusa and Jianshanying slopes were used as supplementary cases to assess the transferability of the proposed framework under more complex geological and topographic conditions. The results indicate that, within the stated simplifying assumptions, the proposed model can reasonably capture the first-order geometry of the subsidence basin, including its asymmetry, peak position, and attenuation trend, with reasonable engineering consistency. Internal friction angle and elastic modulus are identified as the dominant internal controlling factors, whereas slope angle primarily governs basin asymmetry. Overall, the proposed framework provides a simplified yet physically interpretable tool for the preliminary assessment and design screening of slope subsidence under open-pit to underground transition conditions.</p>