The purposes of this research was to understand National Taiwan University students' motivations to participate in soccer courses and to compare the differences caused by gender, class level, course type (elective/compulsory), participation in soccer activities in students' motivations. The research relied on a questionnaire, "Motivations for Choosing Soccer as Physical Education Courses in the Interest-based Course Selection System". The study subjects were the students who took soccer-related curriculum in the second semester of academic year 2005 at National Taiwan University. Based on the 98 valid questionnaires collected. Analyzing data by means of factor analysis, Cronbach α test, descriptive statistics, and t-test, the results were as follows: First, the factors of motivations were "achievement and affirmation", "desire to learn and enjoy", "extrinsic interests", "teacher's teaching", "no other choices". Second, gender, class, course type, and participation in soccer activities had a different impact on the factors of motivation. The conclusions were: First, "teacher's teaching" was the main motivation of the students to take these courses. Second, males students, intermediate-soccer-class students, students choosing the course as an elective and students participating in soccer activities were showing stronger motivations respectively.