Abstract: Wavelet and partial differential equation(PDE) are the main methods in removing image noises.According to both characteristics of denoising,a mixed method of combining wavelet with PDE for image denoising is proposed.Each higher frequency subband is normalized to gain a quantity of continuous states.It is important to pr-otect edge that a continuous state quantity is de noised by means of forward and backward diffusion.We obtain theweight coefficient that is determined by new state quantity after diffusion.The new higher frequency subbands aregained when weight coefficient act on wavelet coefficient.We achieve the process of denoising through wavelet r-econstruction in the end.It is indicated from the experimental results that new method can receive better effect of image de noising and higher SNR than others methods,it attain the purpose of preserving edge and smoothing noi-se at the same time.