Abstract: Facing the comprehensive demands of rapid deployment, long endurance, and high maneuverability for loitering munition unmanned aerial vehicles (UAVs), and addressing the engineering bottlenecks of runway-dependent take-off and landing for fixed-wing UAVs, low cruise efficiency of multi-rotor UAVs, and complex structure of conventional composite-wing schemes, this paper investigates the aerodynamic characteristics of a tail-sitter X-wing vertical take-off and landing (VTOL) UAV. The results indicate that the rear rotor layout can effectively weaken leading-edge interference and replenish the energy of the boundary layer on the upper wing surface, improving the lift-to-drag ratio by 7.6%~8.5% and controlling the thrust deviation within 3%, which reduces the risk of unbalanced rolling moment. For the rear layout, the 280 mm rotor achieves a maximum lift-to-drag ratio of 10.76, which is suitable for high-speed and high-efficiency cruise; the 200 mm rotor reduces the drag coefficient by 3.1%~4.8% and optimizes flow field uniformity, making it more applicable to low-speed and long-endurance missions.