Sweet basil (Ocimum basilicum) plant is one of the commonly used traditional medicinal plants in Ethiopia for treating malaria, headache, and cough. The present study intended to investigate the phytochemicals, antioxidant and antibacterial activities of petroleum ether, ethyl acetate and methanol extracts of O. basilicum leaves. Qualitative phytochemical screening of the crude extracts revealed the presence of phenolics, flavonoids, terpenoids, glycosides, steroids, saponins and tannins. The antioxidant activity was evaluated using 2, 2-diphenyl-1- picrylhydrazyl radical (DPPH) and ferric reducing antioxidant power (FRAP) assays. The total flavonoid content for all the crude extracts was determined using aluminum chloride colorimetric method. The highest total flavonoid content was obtained in methanol extract (83.76 ± 0.02 % mg QE/g), followed by ethyl acetate extract (76.59 ± 0.36 % mg QE/g) and petroleum ether extract (60.46 ± 0.14 % mg QE/g). All crude extracts of O.basilicum leaves exhibited antioxidant activities. The highest antioxidant activity was found in methanol extract (64.65 % in DPPH with IC50 value 38.59 ppm), followed by ethyl acetate extract (59.53 % in DPPH with IC50 value 46.22 ppm ) and petroleum ether extract (53.95 % in DPPH with IC50 value 63.31 ppm). The antibacterial activities were examined using Agar disc diffusion method. All crude extracts showed antibacterial activities against gram negative bacteria (E. coli and K. pneumonia) and gram positive bacteria (S. aureus and S. pyogenes). The result showed that the crude extracts of O. basilicum leaves were more active on gram positive bacteria than gram negative bacteria