For the purpose of optimization on airfoil's aerodynamic performance inlong-endurance UAV (LEUAV), an efficient optimization design approach for the airfoil was proposed, which combined CFD analysis technique with particle swam optimization (PSO) algorithm with radial basis function (RBF) surrogate model method. The airfoil geometry was formulated by orthogonal basis functions method, then by solving N-S formulation, the aerodynamic performance was obtained. The standard PSO algorithm was employed in the optimization in order to improve the global convergence. Due to the higher computational cost, RBF surrogate model was used to approximate to CFD aero-dynamic analysis model to improve optimization efficiency. The results of case studies demonstrate that under the premise of guaranteeing optimization design quality, this approach has reduced computation burden and shortened the design circle, which is also proved to be prac-ticable in engineering.