This study was attempted to investigate antioxidant activities of water and ethanol extract from Rosa multiflora (RM) by in vitro assays measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azino-di-2-ethyl-benzthiazoline sulphonate (ABTS) radical scavenging activity, reducing power activity, nitric oxide (NO) radical scavenging activity, total phenol and total flavonoid content. The water and ethanol extracts from RM scavenged the DPPH radical and ABTS radical in a dose-dependent manner at the concentration range from 10 to 500 μg/ml. The DPPH radical scavenging activity of water extract was higher than that of ethanol extract. IC50 of DPPH radical scavenging activity of water and ethanol extract were 79.73 μg/ml and 145.85 μg/ml. The reducing power activity of water extract was higher than that of ethanol extract. The nitric oxide (NO) radical scavenging activity of the RM extract was similar to their DPPH radical scavenging activity. IC50 of ABTs radical scavenging activity of water and ethanol extract was 79.82 μg/ml and 159.03 μg/ml. The reducing power activity of water extract (0.775) was higher than that of ethanol extract (0.568). Total phenolic content of water extract (140.74 mg/g) was higher than that of the ethanol extracts (37.83 mg/g). Total flavonoid content of water extract (45.31 mg/g) was higher than that of the ethanol extracts (42.68 mg/g). This results suggest that water extract of RM may be useful as potential antioxidant sources.