BACKGROUND: Freshmen maladaptation to university life has brought a lot of attention recently. Therefore, we intended to investigate about the relationship between anxiety, depression, stress and freshmen adaptation to university life. METHODS: We recruited 861 freshmen of a university located in Gyeongju, Gyeongbuk, and measured their degree of anxiety, depression, and stress by questionnaire from March 10 to 14, 2008. After 8 weeks, we examined their adaptation to university life by questionnaire and finally, analyzed the data of 600 freshmen. RESULTS: Among the freshmen, 285 (47.5%) had anxiety, 95 (15.8%) depression, and 70 (11.7%) stress. Adaptation to university life significantly associated with college-entrance exam experience, the number of close friends in class, willingness to join the club, major satisfaction and distance from the university to hometown, in addition to anxiety, depression, and stress. Risk factors of maladaptation to university life were stress (odds ratio: 2.66, 95% confidence interval: 1.60 to 4.45), depression (2.45; 1.56 to 3.84), one experience of college entrance exam (1.83; 1.24 to 2.69), anxiety (1.73; 1.27 to 2.37) and fewer than 5 close friends (1.60; 1.17 to 2.20). Short distance from the university to hometown (0.72; 0.53 to 0.98), willingness to join the club (0.60; 0.41 to 0.87) and major satisfaction (0.42; 0.29 to 0.61) were identified as lowering the risk of maladaptation to university life. CONCLUSION: Anxiety, depression, and stress closely related to freshmen adaptation to university life. During freshmen's health examination, we need to identify the degree of anxiety, depression and stress in order to predict maladaptation to university life.