The purpose of this research is to understand the relationship of psychological well-being, social support, career barrier, and career decision. For this research, high school students from 10th to 12th graders from three different high schools in Gyeonggi-do were surveyed. With ananalysis of 440 surveys, the following is the result: First, while the psychological well-being and the social support showed significantly negative correlations with the career barrier, those with the career decision making level showed significantly positive correlations. The career barriers had a significantly negative correlation with the career decision making level. Thus, higher the psychological well-being and the social support are, lower the career barrier and the higher the career decision making level are. Also, a conclusion can be made from the data that the career decision making level decreased as the career barrier increased. Second, the career barrier acted as a partial mediation between the psychological well-being and the career decision making level, and the career barrier completely mediated between the social support and the career decision making level. Thus, the psychological well-being directly affects the career decision making level, and the social support affects the career barrier depending on the level of making a career decision. In conclusion, the psychological well-being and the social support decrease the degree of a career barrier and act as important factors for positively affecting the career