The protective effects of physical activity and fitness on cardiovascular health have clearly been shown among normally developed children. However, data are currently lacking pertaining to children with developmental coordination disorder (DCD). The purpose of this study was to examine differences in fitness measures, body composition, and physical activity among children with and without DCD. A cross-sectional design was implemented examining 261 children (118 girls, 143 boys) ages 4-12 years (mean age 7.8 [plus or minus] 1.9 years). Children were categorized as having DCD if they scored less than or equal to the 5th percentile (n = 71) or between the 6th and the 15th percentile (n = 52) on the Movement Assessment Battery for Children (MABC; Henderson & Sugden, 1992). The typically developing children had scores between the 16th and the 50th percentile (n = 106) or above the 50th percentile (n = 32) on the MABC. The age-related body mass index was used to characterize body composition. Physical fitness was assessed with a 6-min run, 20-m sprint, jump-and-reach test, medicine ball throw, curl-ups, and sit-and-reach test. Physical activity was estimated with a questionnaire. The percentage of overweight and obese children ages 10-12 years were significantly higher in the DCD groups (severe: 50%, moderate: 23.1%) than in the typically developing groups (medium: 5.6%, high: 0%; p less than 0.05). Significant interactions (MABC x Age Group) were found for the fitness tests (p values less than 0.05), except flexibility; whereby specifically, compared to the children in the typically developing groups children in the DCD groups ages 4-6 years achieved significantly worse results for the 20-m sprint, and children of the DCD groups ages 10-12 years achieved significantly worse results for the 6-min run, jump-and-reach test, and medicine ball throw. The study demonstrates poorer performance in fitness tests with high demands on coordination in children with DCD compared to their typically developing peers. Furthermore, the differences in fitness increased with age between children in the DCD groups versus the typically developing groups. (Contains 3 figures and 3 tables.)