In the practical applications, foot bionic robots have better adaptability and motion performance than the wheeled robots and the tracked robots. In this paper, a hexapod bionic robot system with active olfaction is designed which is based on a foot robot. To find and locate odor sources independently, the system collects gas concentration data by carbon dioxide sensor array which is mounted on the hexapod robot platform. And then the system controls the hexapod robot to move towards the direction of the maximum gas concentration gradient according to the concentration gradient search algorithm. Finally, the experiments proved that the hexapod bionic robot system based on active olfaction is stable and feasible, and can realize the goal of autonomous source-finding.