The respective characteristics of sprint ability of five-year-old infants and adults (university students) were investigated from the view point of the hierarchical factor model. In the experiment subjects ran at full speed along seven different types of 25-meter-courses - straight zigzag (large/small), winding (large/small) and circular (clockwise/counterclockwise). The correlation matrices among running performances of male and female groups of infants and of adults were processed by Principal Factor Analysis on the degree of contribution reaching 60 to 70 percent to total variance, and three factors were extracted in each group of subjects. Then Normal Varimax Rotation was applied to each set of factors, according to ROTO HIST method. The resulted factors for each group were interpreted with respect to each level of rotation. The factors at the third level of rotation, corresponding to lower level of factorial complexity, seemed to exhibit specific running skills in the case of adults, while, in the case of infants, they seemed to be related to the extent of the decrease of running speed for boys, and to exhibit some components of sprint ability for girls. These factors were integrated at the second level of rotation into two factors, which seemed to exhibit the different types of sprint ability, and the similar sex difference was observed in both of infants and adults in these two factors. Concerning the first principal factor, interpreted as the general sprint ability, the degree of contribution to total variance of adults was greater than that of infants. These findings suggest that 1) the extent of differentiation and/or integration of running skills of adults apparently differs from that of infants, and that 2) the basic modality of running control of the male may be different from that of the female, that is, each sex seems to possess an inherent characteristic quite irrespective of their developmental stages.