This study is intended to examine the relationships among life satisfaction, decent work, career maturity, social self-concept, and teacher engagement in high-school graduate workers. For this purpose, data on 356 employed high-school graduates from the eighth and ninth years of the Korean Educational Longitudinal Study 2013 panel survey were used and analyzed. The analysis was performed using descriptive statistics and path analysis with STATA 17.0. Key findings include that life satisfaction among high-school graduate workers statically influenced social self-concept, career maturity, and decent work. Decent work levels showed static influences on career maturity, social self-concept, and teacher engagement, with social self-concept and teacher engagement significantly affecting career maturity. On the basis of these conclusions, empirical studies on the psychology of working theory and subsequent research on the index of decent work are recommended.