In light of the rapid advancements in unmanned aerial vehicle technology, flapping-wing micro air vehicles have garnered significant attention owing to their unique maneuverability and adaptability. Nonetheless, existing designs continue to confront challenges in lift generation, stability, and endurance—particularly with respect to hovering and sustained flight. To enhance overall performance, this study introduces a single-motor driven, hover-capable four-winged flapping-wing micro air vehicle that employs a two-stage spatial four-bar linkage mechanism, thereby achieving a flapping amplitude of 120°. In terms of structural design, critical components are fabricated from high-strength carbon fiber composites and 3D-printed nylon, while finite element analysis, topological optimization, and modal analysis are integrated to strike an optimal balance between weight reduction and structural integrity. The wing design, inspired by the biomechanics of hummingbird wings, incorporates experimentally optimized airfoil configurations along with passive deformation mechanisms to augment aerodynamic performance. Experimental results reveal that under a 12 V supply the maximum net lift attained is 81gf, and when powered by a fully charged 14.2 V lithium battery, the micro air vehicle can sustain flight for approximately 4.2 min. Compared to analogous systems, the proposed design exhibits marked advantages in both lift generation and endurance, thereby laying a robust foundation for the practical deployment of four-winged flapping-wing micro air vehicles.