The present study aimed to determine whether foot clearance is increased by visual illusion during a step-over task. Four participants were asked to judge the height of three obstacles in different conditions [control (i.e., white plane obstacle), horizontal, and vertical illusion conditions] placed 4 meters away from them and then to approach the obstruct to step over it. They perceived the obstacle to be higher in the vertical illusion condition compared to the other conditions. Similarly, they stepped over 83mm to 195mm higher the obstacles under the vertical illusion condition compared to the other conditions. Our results suggest that application of visual illusion can promote the adoption of a safer stepping-over strategy.