The color image is the important expression way of forest plant diseases and insect pests. Based on analyzing the basic process of forest plant diseases and insect pests color image sharpening, it is given that is the color image sharpening process based on the different color space. And the order of gradient operator and histogram equalization affects the sharpening process effect. The experiment results show that the effect of each component of RGB color image histogram equalization is better than the other way. The time of each component of HSI and YCbCr color image histogram equalization is less than the other ways.