Abstract: Affected by functional changes, aging of existing facilities, and the application of new technologies, there is an increasing number of demolition and renovation projects involving old water conservancy facilities, including pumping stations.However, these projects are often constrained by limited construction space, scale, technical processes, and interference from the surrounding environment, making them highly challenging in terms of construction difficulty and safety requirements.To address these issues, this paper proposes a multi-objective optimization method for demolition and renovation schemes in confined spaces.First, an objective function for optimizing the demolition and renovation scheme was established, taking into account safety and spatial impacts.The structural demolition size parameters that satisfy spatial constraints were selected as design variables, and an optimization model for the demolition and renovation of large pumping stations in confined spaces was developed.Subsequently, using the intake channel layer of the Fenghuangjing Large-Scale Pumping Station as an engineering case study, the Pareto solution set for the optimized demolition and renovation scheme was obtained by integrating ISIGHT optimization software with ABAQUS finite element software and applying secondary development based on the NSGA-Ⅱ algorithm.The results demonstrate that, compared to the original scheme, the maximum optimization rates for the safety index and spatial impact index reached 37.801% and 35.015%, respectively, indicating a significant improvement achieved by the proposed method.The relevant experience can serve as a valuable reference for optimizing similar projects.