Combined with the Hyperion hyperspectral image and ALI high spatial resolution band of the EO-1 satellite, the paper puts forward the harmonic analysis fusion (HAF) algorithm of hyperspectral image and the derivative spectral d-value’s information entropy (DSD-IE) model of the spectral-fused information fidelity evaluation. Through calculating and evaluating some parameters such as the DSD-IE values, average gradient and standard deviation of the sample spectra meanwhile compared with the fused hyperspectral images by the traditional methods like the principal component analysis (PCA), Gram-Schmidt and wavelet, the fused hyperspectral iamge by the HAF has proved to have the higher information degree of spatial integration and spectral fidelity, and the better superiorities in the reliability, accuracy and applicability.