How to select the proper method in interference stripes′ data-fitting touches the stripes′ orientation precision and the measurement precision. The limitation of the polynomial least-squareas fitting method is analyzed and a novel method based on the stripes feature is put forward. In this method, the non-linearity problem is resolved. The data-fitting percentage of this method is 99.99% in imitation and 97.24% in experiment. This method can be used effectively in fitting equation to stripes data, the whole data-fitting curve of the interference stripes can be obtained satisfactorily.