The infrared measurement sensor has the characteristics of wide sensing range and narrow effective information scope, resulting in the problems that the conventional gray-scale transformation method may lose effective target information, the low image contrast ratio and poor image quality. According to these problems, an infrared sequence measurement image gray scale transformation method using inverse histogram theory based on gray scale distribution characteristics and processing requirements is proposed. According to the trend of target gray scale, the gray scale scope of the target is expanded, the gray level of the background and the noise is compressed, and the better visual effect is achieved. Experimental results show that the method can preserve complete image background information and the images without distortion, while enhancing the details of the target image.