This study was conducted to confirm the mediating effect of career planning in the relationship between protean career attitude and subjective career success of employed women. It was noted that as the number of cases of women stopping economic activities due to working conditions has recently increased, efforts by the state and society to prevent this are being emphasized. To this end, an online survey was conducted on women in area C from March 6 to April 10, 2023, to secure a total of 159 copies of data, and hierarchical regression analysis and bootstrapping were conducted. As a result of the study, it was confirmed that the protean career attitude of employed women had a positive effect on subjective career success, and career planning mediated them. Based on the results of the study, it was suggested that learning and self-management support is needed to improve the protean career attitude of employed women, and that they should be able to design and implement a series of processes to constantly recognize and grow their careers while in office. At the same time, it was emphasized that approval and support for the career development process should be made together to respond to psychological and emotional problems that appear in the career development process.