Background: In this study, the analgesic effect of aqueous extract of spearmint, which has been used in traditional as an anaigesic anti-rheumatic, medicine was considered.

Materials and Methods: 90 male rats, weighing 200-250 g, were in 10 groups. Aqueous extract of spearmint with different doses including. 0.9, 2.7, 6, 35 and 45 mg/Kg was injected divided. to the experimental animals. the positive control group received Aspirin with diffe the positive control group rent doses of 50, 100, and 300mg/Kg. Normal saline (1ml/Kg) was injected to the negative group. Hot plate method was used for evaluating The analgesic effect of the spearmint extracts and the drug were measured in periods of 15, 30, 45 and 60 minutes after injection.

Results: The results showed that the extract at a doses of 2.7 and 6 mg/Kg has a significant analgesic effect with the highest analgesic effect by the letter. In addition, the results indicated that the 6 mg/Kg of menthe spicata extract was more effective than aspirin 300mg/Kg in the posi tire group.

Conclusion: It seems that dose of the aqueous extract of spearmint has morked analgesic effect and can be considered as a herbal medicine in pain treatment in humen decrease in neuron permeability of Ca++.