Spectral noise induced by the random errors of mirror-velocity and sampling jitter in Fourier-transform spectrometer is analyzed.A model based on Noise Equivalent Radiance Difference(NERD)and Noise Equivalent Temperature Difference(NETD)is established.The analytical results show that the mirror-velocity associated with the amplitude variations and the time delay of the anti-aliasing filter and the sampling jitter can lead to system noise.Then,the noise impact of mirror-velocity and sampling jitter is simulated and calculated by MATLAB;the theoretical model is verified;the noise of the actual instrument is evaluated,which provides the basis for mirror control,anti-aliasing filter design,noise calculation and improvement of Fourier-transform spectrometer.