The purpose of this study was to identify the mediating effects of insecure adult attachment and tact (nunchi) on the relationship between life stress and college adjustment in Korean college students. Methods: A total of 170 college students were recruited into this study and were asked to participate in an online survey. By using SPSS/WIN 24.0, Pearson's correlation analysis was performed to examine the relationships among the variables. The mediating effects were examined by using PROCESS Macro for SPSS Ver. 3.14 model 6. Results: There were significant correlations among the four main variables of this study -insecure adult attachment, nunchi, life stress, and college adjustment. Insecure adult attachment and nunchi mediated the relationship between life stress and college adjustment in college students. Conclusion: Based on the findings of this study, various evidence-based programs can be developed to improve college adjustment and decrease life stress in college students.