It has been established that walking is an attentionally demanding task. However, few studies have examined attentional demands of walking at various speeds and their findings need to be reinforced. Therefore, the aim of the present study was to compare reaction time (RT) at various walking speeds. Fifteen healthy young adults (2 males and 13 females; 20.5 ± 2.59 years) were asked to walk along a 10 meter path at three different walking speeds: preferred, 30% faster and 30% slower. Participants verbally responded to random auditory stimuli as fast as possible while maintaining the requested walking speed. Results demonstrated a significant main effect of Walking Speed on RT (p<0.001). Walking slowly exhibited significantly longer RTs (0.471 ms) than preferred (0.436 ms) and fast (0.401 ms) walking speeds. No difference was found between preferred and fast speeds. Results suggest the longer RTs observed in slow walking could be due to increases in task difficulty, energy requirements and equilibrium demands observed when walking slowly. Since walking fast occurs more frequently than walking slow in daily situations, faster RT in the fast speed condition can be attributed to the fact that it is a more practiced task. The lack of differences in RT between preferred and fast speeds may stem from the similar equilibrium demands. Furthermore, the increase in attentional demand in the non-preferred fast pace may have counterbalanced the heightened arousal levels during fast walking, which could explain the similarity in RT between preferred and fast conditions.