Oxidative stress has been reported to be one of causes of neuritis. This study examined antioxidative activities of methanol extracts of six amphibian species known to be medicinal animals (Rana catesbeiana, R. coreana, R. rugosa, R. dybowskii, R. nigromaculata, and Hyla japonica) and investigated their effects of inhibiting nitric oxide (NO) production and cytotoxicity on the murine macrophage RAW264.7 cells. As inflammation is closely associated with reactive oxygen species, assays on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, xanthine oxidase inhibitory activity, superoxide anion radical scavenging activity and NO scavenging activity of the extracts of the six species were performed to investigate their antioxidative activity. The results obtained were as follows; All extracts showed antioxidative activity, and the activity of R. dybowskii was the highest in comparison among those. Anti-inflammatory effects of the extracts were also examined, the five extracts except that of R. rugosa did not show cytotoxicity for RAW264.7 cells at the maximal concentration ($1,000{mu}g;mL^{-1}$). Selectivity index, meaning NO scavenging activity compared to cytotoxicity, showed the highest level in the extract of R. dybowskii. These results will be very useful basic data for future studies on prevention and treatment of human diseases to understand the biological roles of amphibian extracts throughout the antioxidative or anti-inflammatory pathways.