Instability of satellite platform will seriously affect the quality of spectral imaging. The degradation mechanism of interferential and dispersive imaging spectrometers caused by satellite vibrations is studied in this paper. A simulation algorithm of degradation based on differential dynamic spectral imaging is presented. And the concept of mean mixing ratio (MMR) is proposed, which builds the bridge between the parameters of satellite vibration and the influences on spectral imaging. The quantitative relationship between them is also deduced in detail. Spectral degradation results are simulated by taking the typical spectra and the generated spectrums of surface features as the ideal original data. Simulation results show that the effects caused by pitch and roll are much greater than that by yaw, and the vibrations affect not only spatial resolution but also spectrum, and the regions of rich species are influenced seriously.