The purpose of this paper is to propose a rapid and more accurate method of wing mass estimation for aircraft preliminary design. The wing structure finite element models can be rapidly generated with the method that combined both geometry parametric method and parametric finite element method for the wing structures. The wing structure layout model can be automatically generated by the script of CATIA. Its finite element model can be automatically generated by PCL of PATRAN. The structure size and the mass of wing box structure are computed by optimized method. The examples show that the method can rapidly analyzed the wing mass for different structural layouts and different materials, which is suitable for aircraft preliminary design.