Abstract:Focused on the limitation of traditional image enhancement algorithm, proposed an image enhancement algorithm based on wavelet transform and fuzzy set theory. Firstly, wavelet transform is used to decompose the original image.Secondly, a new membership function of fuzzy was defined and the low frequency coefficient was enhanced by fuzzy enhancement transformation. the high frequency coefficients of different directions was enhanced by wavelet threshold de-noising.Finally, the inverse wavelet transform was applied to restructure image. All algorithms are realized in Matlab. It's can enhance the image effectively and improve image visual effect. The experimental results demonstrate that the algorithm is feasible and effective.