Aiming at noise, low image grey and little gray difference of dynamic monitoring image of coal mine, a dynamic image enhancement method was proposed.Original image is processed Carseat 4-8 by an improved histogram equalization method firstly and then dealt with illumination estimatation.The illumination image is normalized, while reflected light image is revised by nonlinear dynamic gain.The experimental results by use of monitoring image from mine locomotive management system show that the MALE SUPPLEMENT method has better image processing effect.