Using an electro-pedometer which is commercially available, energy expenditure during walking and/or jogging was assessed, and was compared with that obtained by oxygen uptake (VO2). Thirteen male students and 12 female students exercised on 6 minutes duration treadmill tests which velocities were 40, 60, 80, 100, and 120m/min for walking and 100, 120, 140, 160, and 180m/min for jogging, respectively. During exercise, energy expenditure was calculated by VO2 value and respiratory exchange ratio, and was estimated by an electro-pedometer. There was a significant linear relationship between energy expenditures estimated by the pedometer and calculated by VO2 during walking and jogging. To predict energy expenditure more precisely by the electro-pedometer, it is suggested that more precise value of stride should be inputted into the pedometer. In conclusion, the present study showed that commercially available electro-pedometer is able to use for the estimation of energy expenditure with precise validity during walking and/or jogging.