Abstract: Life skills training may enhance achievement motivation of students. This study explores the impact of life skills training on mental health, social adjustment and achievement motivation of female high school students in district 4 Shiraz. This is a quasi-empirical research conducted by pretest-posttest method. The statistical population consists of female high school students of district 4 of Shiraz in school year 2014-2015. Sample size is 170 female students of second year of high school, selected by multistage random sampling method. Data collection tools were California personality questionnaire, achievement motivation questionnaire and mental health questionnaire, together with general point averages of students in the first and second semesters of school year 2014-2015. Life skills training was provided in twelve 90 min sessions on a weekly basis. The results indicated that a significant difference existed between the mean and standard deviation of pretest and posttest scores of mental health and achievement motivation in test group (p>0.05). There was also a significant difference between posttest scores of control and test groups in achievement motivation and mental health (p<0.01). The intervention explained the variance of social adjustment, achievement motivation and mental health by 19. 4 and 72, respectively. Life skills training improves achievement motivation, social adjustment and mental health of female high school students, so particular attention must be paid to life skills training in schools. It is recommended that schools provide students with life skills training and educational consultation services to improve their mental health.