The intensity distribution is inhomogeneous in the interference pattern received with CCD because of the processing errors and agglutination errors produced during researching and processing of the spatial heterodyne spectrometer, which reduces the accuracy of the transform spectrum. An inhomogeneous correction method to interference pattern is proposed through analyzing producing mechanism and characteristics of the inhomogeneity existed in interference pattern intensity of spatial heterodyne spectrometer. According to the method, actual interference pattern was decomposed monotonously, piecewise normalized and recombined to solve light intensity distribution function; then the transform spectrum was convolved with Fourier transform result of the reverse light intensity distribution function to obtain inhomogenous correction spectrum; lastly the inverse Fourier transform was implemented to corrected spectrum to realize inhomogenous correction of interference pattern. The correction method could be used in measured monochromatic interference pattern of near infrared light in spatial heterodyne spectrometer. The results show that the method could effectively improve the homogeneity of interference pattern intensity distribution and inhibit edge frequency signal of transform spectrum. Compared with the simulated ideal spectrum, the noise in 1 571 nm spectrum reduces 40.7% while the noise in 1 572 nm spectrum reduces 24% with signal to noise and accuracy of the spectrum being increased.