The purpose of this study was to investigate effect of 12 weeks mother and child togetherexercise on body-composition, physical fitness, and fellowship. The study involved elementary 1-3 grade 17 students and 17 mother, they were classified bounce group(n=20) and acro group(n=14) according to their choice of subjects. The participants were tested before and after the 12 weeks exercise program for body composition, fitness, and were conducted the survey. As a results, the BMI in child decreased significantly after in comparison with before in a both groups. The strength, flexibility, balance in child increased significantly after in comparison with before in a both groups, agility in child decreased significantly after in comparison with before in a both groups. The muscle endurance in child were significant differences between bounce and acro group. The weight, agility in mother decreased significantly after in comparison with before in a both groups, flexibility in mother increased significantly after in comparison with before in a both groups. The fellowship in child increased significantly in bounce group than acro group in before, and were non-significant differences between bounce and acro group, howeve, tends to significantly increase in after than before. In conclusion, bounce and acro exercise that mother and child together-exercise are effective for improving body-composition and fitness.