The study examined how self-encouragement, support-seeking emotion regulation style and perceived stress impact on psychological well-being in early adulthood. Specifically, self-encouragement through perceived stress affects psychological well-being. At the same time, support-seeking emotion regulation style sets the moderated mediating effect to moderate the impact of perceived stress on psychological well-being and it is verified. The subject of this study were conducted targeting 404 people of early adulthood (age 18∼40) in the metropolitan area. First, it shown to self-encouragement reduces perceived stress. Second, the perceived stress has been found to affect the psychological well-being. Third, self-encouragement influences psychological well-being. Finally, support-seeking emotion regulation style was never an insignificant effect, but perceived stress moderated impact on psychological well-being. This study demonstrated the mediating role of perceived stress in the relationship of self-encouragement and psychological well-being. In addition, the significance is being said that perceived stress and psychological well-being can be adjusted depending on the level of support-seeking emotion regulation style. The results of this study would be expected to provide useful data in counseling interventions in counseling scene for the psychological well-being of the early adults.