Purpose: The purpose of this study is to estimate the impact energy at the landing instant for walking, jogging and running with running shoe and to investigate the correlation between foot strike kinematic factors with impact energy. Methods: A portable impact tester was specifically designed to impact a running shoe (Nike air shox 318684-142) that was positioned on a force plate (AMTI BP400600) with 10 different impact energies (equally distributed from 0.61 to 6.08 joules). The linear regression equation between mean maximum loading rate and impact energy was calculated for this shoe. Fourteen male subjects wearing the same shoes of material test were asked to move across the force plate by walking, jogging and running. The heel velocity, ankle and knee angle at heel strike were measured by using 3D motion analysis system (VisualeyezTM, VZ4000). The impact energies were calculated with the comparison of the ground reaction forces of impact and subject testing. Results: The impact energy for walking, jogging, and running was 0.81±0.45 joule (0.45~1.85 joule), 1.55±0.56 joule (1.07~2.08 joule) and 2.97±1.39 joule (2.06~4 joule), respectively. The kinematic factors: heel velocity(r=0.647, p<0.01), ankle angle(r=0.396, p<0.01) and knee angle(r=–0.478, p<0.01) at heel strike were significantly correlated with impact energy. Conclusions: In future, as using impact testing method to evaluate the cushioning property of the sports shoes, the impact energies should be set at the range from 0.45 to 4.0 joule to simulate the shoe’s cushioning effect under subject walking, jogging and running. Base on the results, the subjects have seemed to adjust their landing strategy to reduce the effective mass at heel strike as the motion speed increased. However, the impact energy still increased because of the greater heel striking speed. In conclusion, impact velocity seemed to have a greater contribution to the increased impact energy than effective mass.