The purpose of this study was to investigate the relationship between career barrier and career maturity of the adolescents who were concretely worried about their career and occupation. 672 middle school students were participated to analyze the Pearson Correlation and Multiple Regression Analyses with data collected by the questionnaire. This study revealed the following results. First, the correlational analysis showed that career barrier associated negatively with career maturity. Second, the multiple regression analysis revealed that sub-elements of career barrier which the adolescents conceived, such as the shortage of self-understanding, the shortage of self-reliance, gender-role conflict and gender discrimination, and the shortage of career and occupational information were significantly effecting their career maturity. Third, as a result of multiple regression analysis to estimate the explanability of career barrier on career maturity, career barrier among various independent factors which were correlated statistically with career maturity showed most effects on it. Also, school academic achievement was confirmed as a significant factor effecting the career maturity. Above these results imply that the perception on the career barrier of the adolescent should be reduced for increasing the career maturity. For this, career education and counselling should be positively intervened and reinforced through the school curriculum and activities.