Dysmenorrhea is the most common gynecological problem and is associated with outcomes such as getting absent from work and school and high health cost. The aim of this study was to compare the effect of Mefenamic acid and Ginger capsules and exercise on primary dysmenorrhea. female students of Mazandaran University of Medical Sciences with primary dysmenorrhea would be selected by random allocation to three intervention groups. Inclusion criteria include: moderate to severe primary dysmenorrhea for at least one day per cycle and exclusion criteria are secondary dysmenorrhea , OCP, IUD, irregular cycle and regular exercise. The initial pain in each group is measured by Visual Analogue Scale. The first group would be received 250mg Mefenamic acid every eight hours and Ginger group 250mg capsule every 6 hours and exercise group a 5 minute exercise exercise, 6 stretching exercise 3 times weekly, for 15 minutes. Pain is measured in groups for 2 cycles.