There is no convincing evidence for the efficacy of moxibustion for primary dysmenorrhea, due to low methodologic quality and small sample size. The investigators designed the random clinical trial to investigates the effectiveness of moxibustion in treating primary dysmenorrhea, the purpose of this study is to provide the research base of moxibustion efficacy. The investigators also examined the acceptability and any adverse effects associated with the use of moxibustion.