Objective: To compare the therapeutic effects of two different moxibustion methods both with tai-yi moxa stick in treating primary dysmenorrhea. Methods: Forty-three patients were randomized into two groups by the random number table according to their treatment orders. The causalgic group was intervened by causalgic stimulation with tai-yi moxa stick while the tepid group was treated by mild thermal stimulation with tai-yi moxa stick. Shiqizhui (EX-B 8) was selected for both groups. Visual analogue scale (VAS) was used for observation before and during the treatment by every 10 min to compare the clinical efficacies between the two groups. Results: Before treatment, there was no statistically significant difference in pain intensity between the two groups (P>0.05). After treatment, both groups achieved significant improvements in pain intensity (P0.05), but the difference was enlarged comparing with that before treatment. The pain relief during the first 10 min of treatment was slower in the causalgic group than that in the tepid group. However, during the later 20 min, the pain relief in the calsalgia group gradually outpaced that in the tepid group. Conclusion: The two moxibustion methods with tai-yi moxa stick both have a good instant analgesic effect in treating primary dysmenorrhea. For patients with primary dysmenorrhea, if 30 min is regarded as the treatment time, mild stimulation was suggested to be used for the first 10 min, and causalgic stimulation for the later 20 min to achieve a better curative effect.