In order to solve the problems of low brightness and low contrast in multispectral satellite images, a remote sensing image enhancement algorithm based on filtering and sharpening is proposed. First of all, according to the linear computation kernel matrix pixel weight characteristics, design of image filtering median filter and Gauss filter based on enhanced operator. Then the first order derivative approximation is used to calculate the intensity gradient, and the gradient of the image is calculated by using the two derivative of the image. Then the image sharpening operator based on Sobel and Laplacian is established. Finally, based on the non local mean algorithm, the image denoising is completed to achieve the purpose of remote sensing image smoothing and enhancement. The experimental results show that: compared with the current remote sensing image enhancement technology, the algorithm has a higher enhancement effect, and better preserves the image brightness and chrominance information