Abstract: In order to overcome the defect that low-night vision device generates monochrome images and to get visual color images more consistent with human eyes, according to the red-green-blue (RGB) color model and spectral separation principle of filters, a system of color night vision based on the secondgeneration image intensifier was designed. Through measuring the spectral transmittance of filter, the impact of filter on the signal to noise ratio(SNR) of image intensifier was educed. According to the low SNR problem, a four-frame fused method of full-wave image was proposed and verified by experiments .The experimental results show that the entropy and variance of chamber image are 6.8 and 35.39, respectively, and that of outdoor image are 7.0, 45.07, respectively, which are all better than the corresponding values of three-frame fused image. The result proves that the method presented is able to overcome the defect of low SNR, and get clearer color night vision image with more details.