Dispersive hyperspectral imaging spectrometer using back-illuminated CCDs will cause interference fringes in near-infrared band, reducing the near-infrared spectral resolution. To solve this problem, we established a multi-beam interference model similar to a Farby-Pérot interferometer, estimated the intensity of distribution of interference fringes from 700 to 900 nm, verified its correctness with measured data, and analyzed the relationship between CCD photosensitive zone thickness and the interference phenomenon. On this base, the authors used the improved flat-field correction algorithm to correct the interference. From 751.83 to 1 010.04 nm wavelength, the correction efficiency can reach 96.6%. The results show that the algorithm can effectively eliminate the interference of dispersive hyperspectral imaging spectrometer in near-infrared band.