"The purpose of this paper is to provide by investigating the impact of their physical fitness and body composition, by comparing normal weight children and Obese Children in the elementary school The Progressive Challenging Physical Activity Program was conducted with background music applied to both groups. Eight weeks later, 5 children and 4 Children. Utilizing SPSS, The progressive exercise program were measured and analyzed repeatedly with the data collected through the activities. The following is a summary of conclusions: First, The result of the eight weeks' the performance of the Physical Activity Program had a positive impact to improve physical fitness for both groups. In particular, physical fitness(cardiorespiratory endurance, muscle endurance, power) was significantly increased in both groups, obese children compared to the normal-weight children had a little noticeable change, but there was no significant difference between the two groups. Second, The progressive Challenging Physical Activity Program had significant and positive effects on the body composition of both groups including weight, body fat, body fat amount, lean body mass, centeral obesity rate and muscle amount, but the difference between the two groups was not statistically significant. key words: Progressive challenging Physical activity, Physical fitness, Body composition, The normal-weight children"