Aiming at the problems of spectral distortion and blurring because of ignoring the image edge information, a Discrete Wavelet Transform (DWT) algorithm based on gradient sharpening is proposed.The IHS transform is used to extract the luminance component from the multi-spectral image, and then DWT is executed on the luminance component and the panchromatic image to acquire the high-frequency and low-frequency subbands.For the low-frequency subband, the gradient sharpening criterion is used according to the edge feature to implement the fusion of low-frequency coefficients.For the high-frequency subband, the way of maximizing the MSE of the pixel region is used to complete the fusion of the high-frequency coefficients.The results are obtained by inverse transformation of DWT and IHS.It is found through experiments that the spectral features and visual effects of the fused remote sensing image are better than that of the current spectral sharpening method.