A longitudinal study was conducted to examine the influence of self-reflection on depression. We looked for a unique effect of self-reflection on depression by eliminating the influence of self-rumination because previous studies showed that the influence of self-reflection was likely to be contaminated by self-rumination. Multiple regression analysis showed that self-reflection significantly reduced the maladaptive effects of negative life events on depression, whereas self-rumination exacerbated those influences of stressors. Although previous studies emphasized that suppression of self-rumination contributes to prevention of depression, this study showed that promotion of self-reflection also can contribute to reducing depression.