The purpose of this study was to investigate the successivechanges of psychological stress in junior high school students at the point of entrance or promotion of grade. Scale on school stressors, cognitive appraisals scale, stress coping scale, and stress responses scale were administered to 423 junior high school students four times each month from April to July. The results of ANOV As revealed that, in general, students lost controllability for study in June and didn t feel much threatened by the stressors in relationship mong friends in July. On the other hand, in April, junior high school students tended to use “active coping” to stressors in study setting and relationship among friends frequently. Moreover, the results of path analyses suggested that stress responses in study setting were better predicted by coping behavior, as stress reponses in relationship among friends were better predicted by cognitive appraisals. Finally, the timing chosen by junior high school teachers to give advice to students and the way teachers instruct students effectively were discussed.