Vascular wall regulates blood flow and pressure, making secure closure of vascular punctures essential in cardiovascular interventions. However, large punctures (>6 mm) under severe bleeding remain difficult to hemostasis and manage and are highly operator-dependent. Here, we present a shape memory vascular wall plug (VWP) that enables autonomous hemostasis through multi-actions of Body, Wing, and Ring functions. VWP is deployed into puncture in a porcine thoracic aorta and activated by warm saline flush to trigger shape recovery. Body and Ring mechanically seal the puncture, while the curved Wing promotes hemostatic sealing and subsequently flattens to maintain physiological blood flow. VWP achieves suturing-level hemostasis with preserved patency and endothelialization. Thrombo-hemodynamic balance is analyzed by computational modeling and validated using whole-blood microfluidic chip, demonstrating a material- and design-driven strategy for large-puncture vascular closure.