The purpose of this study is to investigate the effects of walking exercise intervention on blood biochemical values among obese elementary school students. This study is based on the Puli, Nantou County Elementary School 34 obese students of high classes. Using random groupings, divided them into 17 experimental group and 17control group. Before this experiment, the experimental group and the control group all subjects health-related fitness test and forearm vein blood test. The data for statistical analysis the paired samples t-test and independent sample t-test. The results obtained are as follows: (a) After 15 weeks walking exercise we can find the experimental group intervention on blood biochemical values and sit-ups in health physical fitness are changed. The blood biochemical values are reduced to the level of significance (p <.05); (b) This two independent samples t-test analysis results show us that the experimental group including-flexibility, muscular strength, muscular endurance, cardio-fitness and the other health physical fitness can reach the level of significance (p <.05). Otherwise their body weight, body mass index, cholesterol, triglycerides, blood glucose index are reduced to the level of significance (p <.05). Therefore, After 15 weeks walking exercise intervention will effect the fifth and sixth grade obese elementary school students on their health and fitness, promote healthy weight loss, and blood biochemical values.