The aim of this study was to investigate the effects of psychological independency, self-assertiveness on career attitude maturity focusing on gender difference. The study involved 228 participants(131 males and 97 females) who were asked to complete a questionnaire that measured separation individuation, self-assertiveness and career attitude maturity. Separation individuation was used to obtain a measured psychological independency from parents. The results revealed that there were significant main effects of psychological independency on career attitude maturity. However, main effects of self-assertiveness and gender were not found. There was no interaction of each variable. Subfactors of career attitude maturity were also examined. Among these results, a significant gender difference on independence subfactor. These findings suggested that psychological independency influences on career attitude maturity significantly. The implications of gender difference and limitations of this study were discussed and suggestions for further research were proposed.