Mangrove (including Rhizophora mucronata) is well known as tannin resources either condensed or hydrolyzed tannin. Condensed tannin isolated from other plants has been reported that it have activities as antidiabetic and antioxidant. Therefore, characterization condensed tannin of mature R. mucronata leaves inhibited α-glucosidase and the antioxidant activity were studied. Research method were conducted by extraction condensed tannin to get crude extract, fractination crude extract with different polarities solvent and characterization. The result showed that fractination with different polarities decreased total phenol, total tannin and total flavonoid. However, it rise total condensed tannin from 1.10 mg/100g to 2.06 mg/100g and it was followed by reduction IC50α-glucosidase value from 7.65±0.50 μg/mL to 5.89 ± 0.50 μg/mL. It was lower than IC50 acarbose (10.60 ± 0.20 μg/mL), so it was considered condensed tannin of mature R. mucronata leaves have potency as natural drug to cure diabetic. Fractination of condensed tannin of mature R. mucronata leaves dipped IC50 antioxidant from 491,789.37 ± 427.59 μg/mL to 82,977.11 ± 51.15 μg/mL, but the values was higher from IC50 ascorbic acid (12.36 μg/mL), it can be concluded that condensed tannin of mature R. mucronata leaves did not have potency as antioxidant