In this paper, target tracking is one of the important functions for autonomous mobile robots. To realize this function, stereo cameras are often used. In a general stereo camera, a range image of the entire scene is acquired as precisely as possible, and the image is processed. On the other hand, in this paper, processing is performed by individual cameras according to the requirements, and the results are integrated to acquire three-dimensional (3D) information of only necessary objects. 3D tracking of an object is a specific task. Object detection and tracking are performed by individual cameras, and the results are integrated to acquire 3D tracking information. As a result, erroneous matching can be greatly suppressed, and optimum 3D information for necessary work can be obtained. The effectiveness of the proposed method is verified through target-tracking experiments.