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Background and Objective: The painful menstruation is one of the common disorders of ‎female sexual organ which is experienced by almost fifty percent of the women affected ‎by regular menstrual periods. The primary dysmenorrhea is referred to as the ‎menstrual pain in absence of undetectable pelvic disease which occurs usually during 2 years after first menstruation when ovulation is established. This study was done to investigate the effect of heat and vibration on primary dysmenorrhea. Materials and Methods: This clinical trial study carried out on 75 female students, aged 18-22 years old from Islamic Azad ‎University. Each subject evaluated for two menstrual cycles. At first cycle the participants received the routine pain-relief method. During the second cycle each of them applied combined heat-vibration device for ten minutes during ‎menstrual pain. Data collected using ‎questionnaire and pain visual analog scale and analyzed using SPSS-14, t student and Wilcoxon tests. Results: In contols, pain score was 5.34 and 4.09 prior and after routine intervertion, respectively (P<0.001). Also, in cases pain score significantly reduced from 5.34 to 3.44 after intervention by heat and vibration. In 8% of cases a slight redness was observed. Conclusion: This study showed that heat and vibration is more effective than routine intervention in pain during menstrual cycles.