The connection between human cognitive development and motor functioning has been systematically examined in many typical and atypical populations; however, only a few studies focus on people with Down syndrome (DS). Twelve adolescents with DS participated and their cognitive control, measured by the Corsi-Block tapping test (e.g., visual working memory), the Auditory Memory span test (e.g., verbal working memory) and the Tower of London test (e.g., cognitive planning), and motor control, measured by the Purdue Pegboard (e.g., fine motor control), were measured in this study. Results indicate that if people with DS have better performance in fine manual dexterity, they will have better performance in cognitive planning and verbal working memory abilities. The co-activation hypothesis of the prefrontal area and the cerebellum may support this positive relationship. Hence, it is suggested people with DS will obtain benefits in cognitive control by participating in further motor intervention.