This study aimed to statistically verify the moderating effect of motivation and belief in the relationship between exercise participation intention and actual exercise behavior in order to emphasize individual motivation and belief as a psychological variable that can reduce the “intention–behavior gap,” a phenomenon that does not lead to actual exercise behavior despite having an intention to participate in exercise. To this end, a survey was conducted twice on 141 female pre-service elementary school teachers attending educational universities in Incheon or Gyeonggi-do to measure the weekly exercise frequency, exercise participation intention, self-determined motivation, and “perceived benefit” in the health belief model. The collected data were analyzed using descriptive statistical analysis and correlation analysis, and the moderating effect was verified through hierarchical regression analysis. The results showed that exercise participation intention, autonomous motivation, controlled motivation, perceived benefit, and past exercise frequency were significantly positively correlated with the current exercise frequency. Moreover, autonomous motivation and perceived benefit were verified to have a positive influence on the current level of exercise frequency and were variables that positively control the relationship between exercise participation intention and exercise frequency. This study confirmed that autonomous motivation for exercise and perception of the benefits of exercise are meaningful psychological factors for exercise practice and adherence and suggested the necessity of discussing the direction of pre-service teacher education.