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The present study evaluates the in vitro antioxidant activity of the leaves and stem-barks extracts and fractions of Ochna schweinfurthiana. To this effect, the different extracts were obtained by maceration in four solvents namely ethyl acetate, methanol, acetone and water- ethanol mixture (20-80). The methanol extract which exhibited the best antioxidant activity was partitioned in hexane and ethyl acetate. The ethyl acetate fraction was fractionated by column chromatography with the aid of methyl dichloride/methanol (a€–CHa€—_2 a€–Cla€—_2/ MeOH) solvent system at different polarities. The antioxidant activity of the extracts and fractions was assessed by the 2,2-diphenyl-1-picrilhidrazil (DPPH), ferric reducing antioxidant power assay (FRAP) and the total polyphenol content was evaluated using the Folin-Ciocalteu reagent. The results were analyzed using SPSS 20 presented as mean ± standard deviation. The results phytochemical screening confirmed the abundance of flavonoids and catechic tannins in the methanol and water-ethanol extracts whose content vary between 37.83 ± 1.6 mg ascorbic acid equivalent (EAA)/g dry weight (dw) and 96.4 ±2.33 mg EAA/g dw. The leaves methanol extract possess the best antiradical power (AP) of 0.00114 ± 0.00001 g/mg and the best ferric reducing antioxidant power (542.33±16.51 mg EAA/g dw). The F3 fraction obtained usinga€– CHa€—_2 a€–Cla€—_2/MeOH 5/1 elution system possess the best AP of 0.00125 ± 0.00001 g/mg identical to that of ascorbic acid (AP = 0.00125 ± 0.00002 g/mg) and the strongest ferric reducing antioxidant power (508.66 ± 18 mg EAA/g dw). A positive correlation between the two antioxidant tests and the polyphenols content was obtained. Thus, Ochna schweinfurthiana could be used by the population to prevent some diseases caused by oxidative stress, due to its high antioxidant effect. Key words: Ochna schweinfurthiana, extracts, fractions, antioxidant activity.