This paper mainly examines and analyzes the health and obesity status through a series of body composition testing including body weight, skeletal muscle and body fat. The body composition analyzer is adopted to detect the changes of body com position of college girls after eight weeks of Kung Fu fan PE so as to understand the impacts of short-term exercises about Kung Fu fan on the body composition of these girls. In this dissertation, 90 girls from the college Kung Fu fan PE class are taken as the research object to carry out the physical activity questionnaire and conduct the body composition test in which body weight, skeletal muscle, BMI, body fat percentage are all involved. And then according to the test results, the subjects were split into different groups: normal group, fat-reducing group, muscle-fat reducing group, muscle-strengthening group and muscle-strengthening-fat group to undertake a 8-week physical activity. Eight weeks later, physical activity questionnaire and body composition test would be conducted again to analyze the changes of body composition before and after exercise. Results :(1) The survey before the experiment indicated that the just few female college students remained at a normal level as for body composition, and the extreme types of obesity and emaciation were very obvious. The ratio of the three is 1: 3: 2. (2) Through the low-intensity and long-time aerobic exercise of eight-week Kung Fu fan,obese college students could effectively reduce their body fat, body fat percentage and BMI. (3) Basic metabolism, fat-free weight as well as body moisture index were reduced after eight-week Kung Fu fan exercise. (4)But the effect was not satisfactory in hyperlipemia and muscle groups. Conclusion: (1) Experiment results demonstrates that long-term systematic exercise of kung Fu fans is conductive to the reduction of the fat of the obese. (2) It proves that kung Fu fan exercise for 8 weeks is very effective for muscle growth.