Equal interval sampling of interferogram is realized by a novel uniform sampling method in optical fiber Fourier spectrometer(FFTS).The reference beam and test beam are simultaneously over-sampled.The Interferogram of test beam versus optical path difference is obtained by the relation of sample time versus fringes number and that of interference fringes of test beam versus sample time.Simulation calculation and experimental studies show that the method is effective for eliminating unequal interval sample and many affixation spectra lines.The method can be used in the sample systems not only in FFTS,but also in conventional Fourier spectrometer.Specially,it can also play a significant role in short wavelength Fourier spectroscopy than other methods.