fa Original Article <div style="text-align: justify;"><strong>Background:</strong> Time management skill learning and identification are very effective in the study process, and can reduce the adolescents&#39; waste of time and help them increase the academic achievement. The present study aimed to determine the effect of time management skill on the academic achievement of female students.<br> <strong>Methods:</strong> This interventional study was a randomized controlled field trial. The statistical population consisted of all 2785 female second-grade high school students in 2017-2018 covered by health centers of Gorgan, Iran. Forty eligible students were selected and allocated into intervention and control groups. In the intervention group, a group counseling session of time management training was held for 6 hours in two days. A month after intervention, all students completed the questionnaire, and the students&#39; grade point average (GPA) of the first and second semesters were extracted in 2017-2018. To compare the academic achievement we used the Mann-Witny U test, paired t-test, and Wilcoxon test in SPSS-16.<br> <strong>Results:</strong> The mean of the GPA of students in control group before and after intervention were 17.95&plusmn;1.47 and 17.86&plusmn;1.67, respectively (P=0.43). The GPA in the intervention group was 17.61&plusmn;0.84 before intervention and showed an increase to 17.75&plusmn;1.08 after the time management skill training; but the increase was not statistically significant (P=0.43). The results indicated a statistical significant difference in mean scores of 2 subscales; short-term planning and time attitude in the intervention group in comparison with the control group.<br> <strong>Conclusion:</strong> Despite the fact that time management skill training did not lead to the academic achievement in students, it could improve the short-term planning. Since the follow-up of the present study was short-term, it needs time to improve planning and affecting the academic achievement. It is suggested to examine this assumption in longitudinal and long-term studies.</div> Academic achievement,Adolescent,Time management,Gorgan, 40 43 http://nmj.goums.ac.ir/browse.php?a_code=A-10-1183-1&slc_lang=fa&sid=1 Asieh.Sadat Baniaghil a_baniaghil@yahoo.com 10031947532846009118 10031947532846009118 No Counseling and Reproductive Health Research Center, faculty of Nursing and Midwifery, Golestan University of Medical Sciences, Gorgan, Iran. Maryam Eksir eksirmaryam@gmail.com 10031947532846009119 10031947532846009119 Yes Counseling and Reproductive Health Research Center, faculty of Nursing and Midwifery, Golestan University of Medical Sciences, Gorgan, Iran. Nasser Behnampour behnampour@Yahoo.com 10031947532846009120 10031947532846009120 No Health Management and Social Development Research Center, Biostatistics and Epidemiology Department, faculty of Health, Golestan University of Medical Siences, Gorgan, Iran