Antioxidant activity of fresh and dried Phyllanthus fraternus Webster (Euphorbiaceae) plant materials were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Antioxidant properties of methanolic extracts from shed dried plant showed strong free radical scavenging activity where inhibition (%) observed in aerial parts was 62.89 ± 0.027. The IC50 value of the aerial portions of the plant is 56.12 ± 0.050 where as catechin is 50.51 ± 0.022 at 20µg/ml. Total Phenol and Flavonoid of the methanolic extracts were estimated. Total phenolic content measured by Folin Ciocalteu reagent in terms of catechol equivalent content was 280mg ± 0.035. The total flavonoid content in the Phyllanthus fraternus was also determined by spectrophotometrically and calculated as quercetin equivalent content was 75.5±0.027. Plant phenolics are highly effective for free radical scavengers and exhibit strong antioxidant activity. Result suggests that the plant has great potential in the drug industry as functional drug ingredient.