Introduction: Premenstrual syndrome is diagnosed by recurrent psychological, behavioral and physical symptoms in premenstrual cycle that disappeared one or two days after menstruation. It occurs in 95% of women with various severities and in 5% of women, disrupting personal activities, daily activities, social activities and family relationships. This study evaluated the effects of vitamin E on decrease of muscular pain in premenstrual syndrome. Methods: This double-blind randomized clinical trial was conducted on 75 students who lived in university accommodation of Islamic Azad university of Touyserkan, Iran in 2013. They were randomly divided into two reception groups of vitamin E (n=37) and placebo (n=38). Participants in reception group of vitamin E were use vitamin E capsules 400 unit/day in 7 premenstrual days for 2 month and students in placebo group used similar vitamin E capsules. Pain severity in before and after of vitamin E and placebo use was measured by Visual Analog Scale. Data analysis was carried out using SPSS software version?, Wilcoxon, t-test and Freidman tests. P value less than 0.05 was considered significant. Results: Muscular pain score in vitamin E group was 6.98±1.09 before vitamin use and 4.14±1.14, 2 months after vitamin use. Pain score in vitamin E group had a statistically significant difference in compared with placebo group (p<0.001). Two groups were not significantly different in term of pain severity before taking vitamin E and placebo (p=0.2). Conclusion: Vitamin E is effective on muscular pain reduction and due to having no side effects; it is recommended to be used instead of chemical drugs in muscular pain reduction in premenstrual syndrome.