Abstract: The extracts of buntan (Citrus grandis Osbeck) fruit peel were screened for antioxidant and antimicrobial activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and paper disc diffusion methods. Non-polar extracts exhibited significant antimicrobial activity, while polar extracts exhibited significant antioxidative activity. The ethyl acetate (EtOAc) extract of flavedo were separated with silica gel column chromatography (CC) and four active fractions A, B, C and D (14:1, 9:1, 5:1 and 1:1) were obtained from the eluents of benzene:acetone. The inhibitory activity of isolated compounds using Minimum Inhibition Concentration (MIC) against Gram-negative and positive bacteria strong antimicrobial was recorded as follows oxypeucedanin hydrate (100-290 ppm), oleic acid (150-350 ppm), meranzin hydrate (620-850 ppm) and linoleic acid (700-950 ppm). The antioxidant inhibition concentration 50% (IC50) for isolated components strongest activities were recorded as follows sitosterol linoleate described as a new isolated compound from the plants (95 ppm), meranzin hydrate, (160 ppm), isomeranzin (245 ppm) and oxypeucedanin hydrate (330 ppm) was recorded.