A protein fraction isolated from green algae Halimeda macrobola taken from the sea of Selayar and Kapoposang Island inSouth Sulawesi was tested forantioxidant and anticancer properties.The protein was isolated using buffer Tris (hydroxymethyl) amino methane. Initial purification of protein uses conducted by using the fractionation method with ammonium sulphate, followed by a dialysis process. The protein concentration was determined by Lowry method. The antioxidant assay was done by using DPPH method and the anticancer activity test by Brine Shrimp Lethality Test (BSLT) methods. Anticancer activity was further confirmed by antimitotic test using urchinzygote cells. The results showed that the protein concentration of the crude extract was 0.920 mg/mL. The highest concentration of protein fractions was indicated by the fraction 40-60%,with 1.015 mg/mL. The strong antioxidant activity wasnshown in the protein fraction of 0-20% saturation with IC50 values of 0.110 mg/mL.The highest activity in the anticancer tests was shown in fractions 0-20% saturation with LC50 values of 0.29??g/mLand IC50 value of 53.80 ??g/mL. The protein fraction 0-20% saturation had a potential to be developed as an alternative antioxidant and anticancer agent
