Kinetic energy of human locomotion was measured when he walked under hypogravic condition. the equipments and calculating method used for this study are summarized in this report. The hypogravic condition was simulated by pulling a man upward with constant force using special harness fitted to human body and a spring pulley device to make as constant force as possible. The pulley can move along a rail so that the subject can walk under the simulated condition. The kinetic energy was calculated for several walking speeds from the data of accelerometer mounted on the harness and stepping forces measured by two three-dimensional load cells.