Objective: To observe the clinical effect in the treatment of toothache by puncturing Hegu(LI 4). Methods: Two hundred and seventy-eight cases of the patients were randomly divided into the treatment group (139 cases) and the control group (139 cases). The treatment group was treated by puncturing Hegu (LI 4) with electric stimulation and the control group, by puncturing Chenshan (BL 57) with electric stimulation, for 3 days as one course of the treatment,to grade pain and observe the anesthetic effect respectively. Results: There was no significant difference in the remarkable effective rate between the two groups before withdrawal of the needle in the treatment for one day (P>0.05). In the other times, the remarkable effective rate was obviously higher in the treatment group than in the control group (P<0.05). Conclusion:Acupuncture on Hegu (LI 4) is effective in treating toothache.