Aiming at the optimal aerodynamic shape of the airfoil, a continuous deflection deformation law for the leading and trailing edge of an airfoil combining multiple-parameter deflection and B-spline was proposed. Taking NACA3412 airfoil as an example, the parametric reconstruction of airfoil curve was carried out. Numerical simulations were adopted to analysis the influence of the deflection position and angle of leading edge and trailing edge on the aerodynamic performance of the airfoil. Take the airfoil lift-to-drag ratio and lift coefficient as the optimization targets, and with six deflection parameters, including leading edge deflection angle, leading edge deflection position, leading edge transition section length, trailing edge deflection angle, trailing edge deflection position and trailing edge transition section length as the design variables, the multi-objective genetic algorithm NSGA-Ⅱ, and ANSYS software were used to optimize the variable-camber airfoil. Compared with the basic airfoil, the lift-drag ratio of the optimized variable-camber airfoil was increased by more than 19.26% while the lift coefficient was increased by more than 44.43%.