<p>Cylindrical shell structures, known for their light weight, high strength, and excellent load-bearing capacity, find extensive applications in aerospace, bridge engineering, and other fields. Under extreme service conditions, however, defects such as cutouts can emerge and compromise both stability and load capacity. This study combines quasi-static tensile experiments with finite-element simulations to quantify how cutout radius, spacing, and angular arrangement influence residual load-bearing capacity and fracture morphology. The results indicate that the presence of cutouts significantly reduces the residual load-bearing capacity of the shells, and different combinations of cutout parameters lead to varying fracture paths and changes in load-bearing capacity. In particular, changes in cutout size and spacing alter stress-concentration intensity and overlap, while variation in angular arrangement governs ligament failure modes, yielding nonlinear “slow–fast–slow” capacity responses. By correlating stress-field evolution with crack initiation and growth, the underlying fracture mechanisms of perforated cylindrical shells under tensile loading are elucidated. These findings provide a theoretical basis for engineering design and safety assessment.</p>