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Background: Oxidative stress is one of the probable molecular mechanisms involved in lead (Pb) neurotoxicity. On the other hand, lemon balm (Melissa officinalis) which is widely used in traditional medicine, has a high antioxidant activity. In this study, the protective impacts of Melissa officinalis on the adverse effects of Pb toxicity on learning ability were investigated. Materials and Methods: In this experimental-clinical trial, 40 virgin Wistar rats were mated and divided into control, control positive (vitamin C+Pb), control negative (Pb), and 3 Pb and Mellisa experimental groups. Mellisa was orally administered in three doses including + 25, 50 and 100 mg/ kg of body weight daily. Treatment started from 7th day of gestation and continued through pregnancy and lactation periods. The three month- old offsprings in each group were assessed in terms of memory and learning ability by Morris water maze test and the results were compared between the groups. Results: Exposure to Pb during and after gestation leads to learning disorders. While concomitant administration of Pb and Melissa, as well as vitamin C can, to a large degree, reduce the adverse effects of Pb on learning abilities. Conclusion: Since no significant differences were obtained from the comparison of results in the control, Pb+M and vitamin C+Pb groups, it can be concluded that Melissa has antioxidant impacts equal to vitamin C. Therefore, similar to vitamin C, Mellisa can decrease the neurotoxic effects of Pb.