The purpose of this study was to explore the critical factors that influence the elementary school students' intention of participating in sport camp during summer vacation. This study decomposed belief constructs of the Theory of Planned Behavior(TPB;Ajzen,1985) generating the Decomposed Theory of Planned Behavior(DTPB) to develop the research model and accordingly designed the questionnaire. Research participants included 532 elementary school students from the fifth and sixth grades (age 10-11 years) from Taichung County, Taiwan. Data was analyzed by using structural equation modeling (using LISREL8.50). The results showed that the research model had an acceptable fit with the data and the DTPB model could be used to examine the hypothesized relationships among the variables. The percentage of behavior intention could be explained by Attitude, subjective norm and perceived behavioral control was 0.58. Attitude, subjective norm and perceived behavioral control all have a significant and positive effect on behavior intention. The behavior intention was most strongly determined by perceived behavioral control, whereas the influence of attitude is relatively weaker. In addition, through the decomposition approach this study found that attitudinal components (instrument beliefs, affect beliefs and risk beliefs) subjective norm components (primary normative beliefs and secondary normative beliefs) and perceived behavioral control components (self-efficacy, facilitating conditions and barriers conditions) had significant indirect effects on intention to participate in sport camp. The results also supported the view and hypothesis of this research. Based on the results of this study, the managerial implications and application were discussed, the solid recommendations were made to the relevant government agencies and the sport camp managers such that they can use the information as a reference on their planning and execution. Some suggestions were also offered for future research.Keyword(s): elementary education, physical activity, sport management