To address the limited endurance of Flapping-Wing Aerial Vehicles (FWAVs), this paper proposes the integration of highly efficient triple-junction gallium arsenide (GaAs) flexible thin-film solar cells into the wing structure of a bionic “Dove” flapping-wing aerial vehicle. Through static loading tests, wind tunnel experiments, and field photovoltaic performance tests, we systematically evaluate the variation in stiffness, the impact on aerodynamic performance, and the photoelectric conversion capability of the solar wing structure. The results indicate that the integration of solar cells significantly enhances the local stiffness of the wing area, effectively suppressing structural deformation and improving lift retention capability under high-frequency and high-wind-speed conditions. However, under low-frequency or high-angle-of-attack states, flexible deformation is restricted, leading to a slight decrease in lift and thrust. In practical testing environments, the conversion efficiency of solar cells remains stable at approximately 20%, meeting the operational requirements for low-power payloads. When integrated with a Maximum Power Point Tracking (MPPT) system, this setup enables dynamic energy supply and management. This study validates the potential of integrating solar systems with bionic flapping-wing structures, providing theoretical support and experimental evidence for the development of flapping-wing flight platforms with autonomous energy supply and long-endurance capabilities.