This study examined the antioxidant and neuronal cell protective effects of the water and methanol extracts of Eugenia caryophyllata Thunb. The total polyphenol content was significantly higher in the methanol extract than in the water extract. The DPPH radical scavenging activity in the water extract was similar to Vit. C at a concentration of 100~200 μg/mL. The ABTS radical scavenging activity in the water and methanol extract was similar to Vit. C at a concentration of 800~1,000 μg/mL. The superoxide dismutase (SOD)-like activity in the methanol extract was similar to Vit. C at a concentration of 800~1,000 μg/mL. The DPPH, ABTS radical scavenging and (SOD)-like activity increased with increasing extract concentration. In a cell viability using MTT, the water extract (50 and 100 ppm) and methanol extract (100 ppm) had a protective effect against H2O2-induced neurotoxicity.The result ssuggest that the extract of E. caryophyllata Thunb. has antioxidant activities and may be useful for treating neurodegenerative disorders.