This study aimed to determine the efficacy of acceptance and commitment based therapy (ACT) on depressive symptoms and cognitive emotion regulation strategies in depressive students. The research method was a quasi-experimental study with a pre test, post test, follow-up design and a control group. The sample was selected by multistage sampling and included 40 students who were matched by age, educational status, lack of mental or physical diseases, clinical interviews and by scoring over 19 on the Beck Depression Inventory, Second Edition (BDI-II) along with other criteria considered in this research. The participants were randomly divided into a control and an experimental group. The research instruments included the BDI-II and cognitive emotion regulation questionnaire (CERQ). The experimental group received eight sessions of ACT and the control group did not receive intervention. The results showed a significant difference between groups in terms of depression and CER strategies (p< .01). The rate of depression and negative CER strategies in the experimental group was significant lower than in the pre-test and control group and their positive CER strategies were significantly higher. These 6results were persisted significantly to the follow-up period. The present study showed that ACT effectively reduced depressive symptoms and negative CER strategies and increased positive CER strategies in depressive students.Keywords: acceptance and commitment based therapy (ACT), depressive symptoms, cognitive emotion regulation strategies Depression is one of the most common disorders that mental health providers are called upon to treat (Young, Rygh, Weinberger & Beck, 2008). Epidemic studies have reported depression to be the most common mental disorder (Segal, Williams & Teasdale, 2002). Approximately about 20 to 25 percent of women and 10 to 17 percent of men are affected by depression during their lives (Kessler, Berglund, Demler, Jin, Koretz, Merikangas, Rush, Walters & Wang, 2003;Levinson, 2006;Eilenberg, Hoffmann, Jensen & Frostholm, 2017). This disorder is often chronic and relapsing, each succeeding episode of depression increases the risk of another occurrence (Kessler et al., 2003).Recent estimates suggest that50 to 60 percent of people who experience an episode of depression will experience a second episode,70 to 80 percent of those will experience a third episode and 90 percent of people who have had three episodes of depression will experience a fourth episode (American Psychiatric Association, 2000;Burcusa & Iacono, 2007).The student population is an important social group that is at risk of depression (Buchanan, 2012). Studies show that students who suffer from depression have experienced more difficulty in their academic work and they obtain lower grades than nondepressed students (Lyubomirsky, Kasri & Zehm, 2003;Moyer, Murrell, Connally & Steinberg, 2016). Generally, depression issignificantly related to reduced academic performance (Hysenbegi, Hass & Rowland, 2005) Saules-Cranford & Eisenberg, 2...