Abstract: In order to achieve efficient, safe, and economical utilization of karst depression sites, this study applies multi-objective optimization theory, considering various constraints such as terrain, geological conditions, and economic factors, to optimize the excavation parameters of arc-shaped slopes. A method for spherical cap surface fitting and crown-bottom position optimization is proposed. By constructing an optimization model with the objectives of maximizing spatial utilization and minimizing excavation and fill volumes, optimal excavation parameters are selected, resulting in three alternative plans. Subsequently, numerical simulation techniques are employed to analyze the deformation, plastic zone distribution, and stress variations of the arc-shaped slopes after excavation for each plan. Targeted anchoring reinforcement solutions and support quota calculations are designed. A comparative analysis of four key indicators—spatial utilization rate, excavation and fill volumes, slope stability, and support costs—reveals that under the premise of considering slope stability and engineering cost, the optimal choice is to design and optimize the excavation layout scheme. This research provides a systematic optimization approach and practical guidance for the excavation design of complex karst depression sites, offering significant engineering value. It also presents reference design concepts and cost control strategies for similar projects, contributing to improved karst landform utilization efficiency and reduced project risks.