Abstract: Objectives This study investigates the residual compressive performance of composite sandwich panels after damage repair through experimental and numerical approaches, with parametric analysis conducted to develop repair strategies for enhancing residual compressive strength. Methods Test specimens were prepared using manual scarf repair hand-layup techniques, and axial compression tests were performed on both repaired and intact panels. Based on the Hashin failure criterion, progressive damage model, volumetric hardening model, and cohesive zone model, a progressive failure analysis was developed to examine the residual compressive strength and failure mechanisms. The effects of scarf angle, overlay size, and patch ply orientation on the repair effectiveness were systematically analyzed. Results Results demonstrate that the established progressive failure model accurately simulates the damage evolution process in repaired composite sandwich panels, with less than 7% error in ultimate load capacity between simulation and experiments. The primary failure modes of repaired panels were patch debonding and fiber fracture. Conclusions The scarf repair technique effectively restores the residual compressive performance of composite sandwich panels, optimal repair effectiveness was achieved with a scarf ratio of 1:10, an overlay diameter 1.2-1.3 times the patch diameter, and patch ply orientations consistent with the parent laminate.