The purpose of this study was to examine a relationship between the degree of liking and disliking of sport and physical activity, and stress development.We conducted a survey on Japanese junior high school students (129 boys, 139 girls) in 2007. The survey included such entries as 1) positive vs negative attitude toward physical education classes, 2) the degree of physical education classes-related stress, and 3) personality qualities (goal orientation, sports competence and active coping).In our survey concerning the degree of predilection for physical education classes, the results were as follows: 171 subjects in Group A said they liked physical education classes; 39 subjects in Group B said they didn't like and 57 subjects in Group C chose "neither". Comparing the degree of stress from physical education classes, Group A scored significantly lower than the others by Tukey's multiple comparison test (p<0.05).Also, in order to find the key factor which determines the degree of liking and disliking of physical education classes, we measured various values among 52 subjects with a high degree of stress as a dependent variable, and analyzed the personality aspects as an independent variable. As a result, we found a negative correlation between stress levels and sports competence, whereas ego orientation and active coping had a positive effect on the degree of stress.We showed that those liking physical education experienced low degrees of stress. Conversely, those individuals disliking sport and physical activity should not be expected to experience reduced stress while participating in sports. Furthermore, we can indicate sports competence as a determinant of stress reduction. Consequently, in order to stimulate regular participation in sports activity and to release its stress-reducing potential, it is necessary to develop childhood physical education classes to foster sports competence.