The invention discloses a fixed-wing unmanned aerial vehicle outer wing structure and a manufacturing method thereof. The fuel economy and the market competitiveness of a fixed-wing unmanned aerial vehicle are effectively improved. The outer wing structure comprises a wing box, the rear end of the wing box is connected with a wing flap, an aileron and a winglet, the front end of the wing box is provided with a forward uplifted front edge inner section and a front edge outer section, the wing box is provided with an upper wall plate, a lower wall plate, a front beam, a rear beam, a wing rib anda joint, the joint is used for connecting an outer wing with a central wing, horizontally extending foam stringers are arranged on opposite surfaces of the upper wall plate and the lower wall plate,grooves matched with the foam stringers are formed in the upper end and the lower end of a middle wing rib, the front beam and the rear beam are in 'Z' shapes, lower plates of the front beam and the rear beam oppositely extend and are fixed onto the lower wall plate, upper plates of the front beam and the rear beam reversely extend and are fixed onto the upper wall plate, web plates of the front beam and the rear beam are connected between the upper plate and the lower plate, and the wing rib comprises a front wing rib, the middle wing rib and a rear wing rib.