Background: Nitric oxide and reactive nitrogen species play an important role in various pathological conditions like cancer, inflammation and neurodegeneration. As plants and natural compounds have a great potency of discovering lead compounds which might affect NO production during inflammation and various pathologies, we examined the effects of three medicinal plants native to Iran, on NO production during oxidative stress in PC12 cells. Methods: In this study, cell death and NO levels were measured by MTT and by Griess assay, respectively. Oxidative stress was induced by hydrogen peroxide and extracts of Astragalus jolderensis, Convolvulus commutatus and Salvia multicaulis were used as pretreatment in oxidative stressed PC12 cells. Results: A. jolderensis extract significantly suppressed NO production in 150 and 200 μg/ml concentrations and C. commutatus extract in all concentration inhibited NO production in stressed PC12 cells. In addition, the extract of S. multicaulis inhibited NO production during stress at all concentrations above 50 μg/ml. Besides, the extract of S. multicaulis showed protective effect at lower doses in stressed cells. Conclusion: According to the results, S. multicaulis inhibited NO production and protected cells from oxidative stress. Hence, S. multicaulis is a good candidate for further in vitro and in vivo investigations. A. jolderensis and C. commutatus also suppressed NO production during stress. Therefore, they could be noticed in experiments that centralize on the inhibition of NO production and drug discovery studies in the field of neurodegenerative and chronic inflammatory diseases.