Some disease in the body are caused by free radicals. Antioxidant are compounds that a play a role in suppressing indicator of the formation of free radicals. One of the plants that contain natural antioxidant is the mangosteen leaf (Garcinia mangostana L.). Method : This study aims to determine the antioxidant activity of the ethanol 50%, 70% and 96% extract of mangosteen leaf (Garcinia mangostana L.) using the FRAP and BCB methods with a ratio of quercetin and ascorbic acid as a comparison and then calculating IC50 value. Determination of total phenolic content was measured by UV-Vis Spectrophotometer using Follin-Ciocalteau reagent. Result : The result showed that the total phenolic content of the ethanol 50%, 70% and 96% extract of mangosteen leaf (Garcinia mangostana L.) were 26,27 mgGAE/g, 30,62 mgGAE/g, 40,37 mgGAE/g. The antioxidant activity of the FRAP method content of the ethanol 50%, 70% and 96% extract of mangosteen leaf (Garcinia mangostana L.) is a very strong antioxidant group because it produces IC50 of 48,97 μg/mL, 24,24 μg/mL and 21,19 μg/mL. Ascorbic acid as comparison is a strong antioxidant because it has an IC50 of 68,24 μg/mL. The antioxidant activity of the BCB method content of the ethanol 50%, 70% and 96% extract of mangosteen leaf (Garcinia mangostana L.) is a very strong antioxidant group because it produces IC50 of 40,61 μg/mL, 27,21 μg/mL and 21,53 μg/mL. Quercetin as comparison is a very strong antioxidant because it has an IC50 of 6,97 μg/mL.