At present, the cleaning robot presents an intelligent situation, which can realize map building, path planning, self-charging and so on. Taking the coverage rate of intelligent cleaning robot as the research object, real-time image is used to test and analyze the target.In this method, the collected real-time image is transformed into segmented gray scale. The target is identified by template matching, and the motion path is measured by sub-pixel edge location. Thus the coverage of the cleaning robot can be calculated. Experiments show the effectiveness of the proposed method.