Background: The aim of the present study was to determine the association between cardiovascular fitness and body fat accumulation and distribution in children and adolescents aged 7 to 17 years. Material and methods: The sample was composed of 1,625 boys and 1,244 girls. Maximal aerobic power was determined through the Course Navette running test. Anthropometric evaluation was previously performed to establish the total amount of subcutaneous body fat accumulated (the sum of six skin folds) as well as the quantity of subcutaneous fat accumulated on the trunk (sum of 3 trunk skin folds). The subjects were divided into 2 groups according to cardiovascular fitness. Those with lower VO 2 max values (last two quintiles) comprised the low cardiovascular fitness group while those with VO 2 max values between the two highest quintiles comprised the high cardiovascular fitness group. Results. Differences were adjusted for age, height and body mass. In both boys and girls, better cardiovascular fitness was associated with a significantly lower amount of subcutaneous fat not only on the entire body but particularly on the trunk. Conclusions. Girls and boys with better cardiovascular fitness showed a healthier body composition and lower risk of cardiovascular accidents. Fitness level should be included in health risk evaluation in the populations studied.