In this paper, an integrated automatic stereo target-detection system is proposed, in which a stereo camera embedded on the mobile robot system is employed and using this system a potential 3D target object is detected and discriminated from the other objects and backgrounds, and then its moving trajectory and direction data is transferred to the host vehicle so as to warn a potential collision with a target to the UGV (unmanned ground vehicle). The face area of a target person can be tracked by using the YCbCr color model, centroid method and the depth map. In addition, a distance and area coordinates of the target face can be also calculated, in which the calculated coordinates are used for extraction of 3D information that can be used for plan paths, construction of the coordinates maps and exploration of the indoor environment. From some experiments on person tracking by using the sequential stereo image pairs of 1,280 frames, it is analyzed that error ratio between the calculated and measured values of the distance is found to be very low value of 0.7% on average.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.