Keywords: Keywords: Aloe Vera, Tumor necrosis factor- alpha, Experimental autoimmune encephalomyelitis, Multiple sclerosis, C57BL/6 mouse,

The University is a stressful place can cause depression symptoms and it's a critical context for studying of students’ psychological health. Because of moving away from family, living with other students, academic atmosphere pressures and uncertain future, students are often in risk of depression. This study was done to determine prevalence and related factors of depression in students of Arak, Iran. This analytical cross-sectional study was carried out on 304 undergraduate medical and basic students in Arak universities, from May to July 2008. General Health Questionnaire -28 question (GH-28) has been used for data gathering and analyzed by T-test, chi2 and logistic regression tests. Mean of student's general health was 26.18±11.02 and 52.3% of students were scored above the threshold of GHQ- 28, that indicating depression. Female sex, major uninteresting, uncertain future and positive family history were the most important risk factors of depression but significant relationship between age, education Course and year were not seen. The prevalence of depression was higher than society and in girls is more than boys students. But there wasn’t any difference between medical and non medical students. So attention to financial and occupational future of graduated and under graduated students is essential.