In order to accurately estimate chevron curved surface, bilinear interpolation fitting method to calculate was applied. Using triangulating bilinear interpolation function fitting chevron curved surface function, the curved surface area calculation about chevron curved surface was translated into the corresponding subdivision surface area of the calculation of triangulating bilinear interpolation functions, thus the area of chevron curved surface approximate calculation formula and a numerical example was given. Further the calculation precision of the approximate calculation was discussed in the thesis, and finally presenting a numerical example, the numerical results show that the validity of the formula.