The invention discloses an image de-noising method based on bidirectional enhanced diffusion filtering, which simplifies a diffusion equation. The method comprises the steps of establishing a bidirectional diffusion coefficient so that a model can implement a bidirectional process of smoothing and sharpening in the diffusion process, enhancing an image in order to further improve the smoothing and sharpening strength, performing wavelet transform to enhance the overall outline of the image and weaken texture details of the image, then adaptively designing and improving a gradient threshold to automatically control the gradient threshold according to the maximum gray value and the iterative times of the image and further retain edge and detail features of the image, finally, simulating the purposed model, and performing simulation verification on the method by using MATLAB software. The method can be used for removing image noise and protecting detail information of edge, texture and the like, greatly improves the peak signal to noise ratio, has more excellent de-noising performance, and has a good application prospect.