We have developed a visually controlled bipedal running robot named ACHIRES: Actively Coordinated High-speed Image-processing Running Experiment System. This robot has a leg length of 14cm and 6 degrees of freedom, and can run in the sagittal plane at 4.2 km/h . Its key technologies are high-speed vision for recognizing the posture of the robot at 600 fps, and high-speed actuation for realizing high speed motion. The combination of these technologies plays an important role in the robot’s ability to run stably at high speeds.