The antioxidant capacity of fruits is related to the delay of aging and prevention of various diseases due to these fruits' capability to react with free radicals and protect the tissues of the human body against oxidative stress and associated pathologies. Thus, this work aimed to determine the antioxidant activities of Brazilian native fruits. Fruits were obtained from several regions: North (Belém-PA); Northeast (Salvador-BA and Fortaleza-CE); Midwest (Goiânia-GO and Campo Grande-MS); and South (Pelotas-RS). From the fruit pulps, methanolic extracts were obtained for the determination of the antioxidant activities by measuring absorption of the free radical ABTS (2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid)) at 734 nm after 6 min of reaction time. Results were calculated using a standard Trolox (5,7,8-tetramethylchromane-2-carboxylic acid) curve and then expressed as wet weight of fruits (mmol Trolox.g-1). The antioxidant activities of the fruits ranged from 10.03 to 0.38 mmol Trolox.g-1. The antioxidant capacity for each analyzed fruit was: Açaí (10.03 ± 0.84), Pupunha (1,51 ± 0,03), Cupuaçu (1,05 ± 0,12) [North]; Maxixe (1,13 ± 0.01), Sapoti (0.57 ± 0.08), Cajá (1.49 ± 0.2), Carambola (2.36 ± 0.11), Genipapo (5.66 ± 0.28), Cajarana (1.81 ± 0.09), Biri-biri (1.90 ± 0.06) [Northeast]; Pequi (1.83 ± 0.03), Cajá-manga (1.52 ± 0.10), Jatobá (6.37 ± 0.13), Pitaya (0.75 ± 0.07), Granadilha (0.86 ± 0.07), Kino (0.38 ± 0.18) [Midwest]; Jambolão (5.92 ± 1.64), Butiá (3.92 ± 0.73), Caqui (0.52 ± 0.06), Goiaba (7.99 ± 1.9), Bananinha do mato (1.58 ± 0.23), Lima (4.26 ± 0.09) and Pessêgo (1.71 ± 0.05 mmol Trolox.g-1) [South]. Finally, the results presented in this work contribute to knowledge of the antioxidant properties of fruits that are consumed in Brazil, directing the choice of products containing medicinal potential.