Poetry therapy may be considered a form of "creative art therapy" through which, by the use of poetry and other motivating forms of literature, the goals of therapy and personal growth may be achieved. Some studies have shown that the positive effects of poetry as a therapeutic modality on some mental and physical diseases. The aim of the present study was to investigate the effectiveness of group poetry therapy on irrational beliefs in female undergraduate students with depression signs. Material and methods: A quasi experimental method was employed using a pre and posttest design frame work and a control group. After screening a target population consisting of all female undergraduate students at Shahid Beheshti University during the second term of 2008 – 2009 academic year, a sample of 29 participants were randomly assigned to either an experimental group (n = 14) or a control group (n = 15). The experimental group took part in seven session of group poetry therapy of 90 – 120 minutes duration each while the control group was put on a waiting list. Variables were measured using the Irrational Beliefs Questionnaire (IBQ) before and after intervention. Data were analyzed using SPSS and Mann Whitney non parametric test was conducted. Results: Results showed that poetry therapy plays a significant role in reducing irrational beliefs (p=.001). Conclusion: Using the poetry as a therapeutic modality can prompt the thought flexibility in students having depression symptoms thus confirming previous research conducted in the field and suggests psychotherapists using poetry especially in Iran considering the literature importance in Iranian culture.