The main purpose of this study was to examine effects of exercise intervention on upper-grade pupils' body image, self-esteem, and physical activity. The self-administered structured questionnaire developed by Bi-Sia Li and Jing-Min Chen (2004) was used to gather data from 38 fifth-grade students and 18 sixth-grade students of an elementary school in Kaohsiung City (age: 10.64±0.59 years old; height: 1.48±0.08 meters; weight: 48.91±10.49 kilograms; BMI: 22.16±4.16), and the study was conducted in the form of an empirical study. Research subjects were divided into the experimental group and the control group. The experimental group was given a forty-minute exercise intervention three times a week for a period of five weeks, and at the same time asked to fill out a questionnaire about body image, self-esteem, and physical activity before and after the intervention. The data obtained was combined with the designed two-way (group * pre- and post-test) ANOVA to examine the difference in effects of exercise intervention on upper-grade pupils' body image, self-esteem, and physical activity, and the significance level was set as α=.05. As research findings indicated, research subjects had positive perception of body image, and significant difference was also observed in the comparison between the pre-and post-test of the two groups. Thus, inferred from the aforesaid findings, exercise intervention enhanced the experimental group's perception of body image; upper-grade pupils had self-esteem above the average, which made no significant difference between the experimental group and the control group. Thus, exercise intervention had no significant effects on changing self-esteem. Research subjects had higher levels of physical activity, which made no significant difference between the experimental group and the control group, and exercise intervention had no effect on changing the ability of physical activity. In conclusion, further studies with the duration and intensity of exercise intervention, a larger sample size, and a discussion on different influential factors are recommended, and the improvement should be made based on different influential factors in order to enhance personal body image and self-esteem, and to improve both physical and mental health of nationals in Taiwan.