Banana and plane are the most important fruits in world trade, behind citric plants. In this work we studied the antioxidant capacity of banana and plane varieties of fruits obtained from interspecies crossed varieties of Musa acuminata and Musa balbisiana, named Harton plane, Cavendish banana, and Manzano banana. With this purpose we evaluated banana and plane crude extracts using the ferrous ion oxidation with xylenol orange method, the thiobarbituric acid method, determination of antioxidant activity, and effect on superoxide anion and hydroxyl radical and the radicals generated by ultraviolet light. The experiments showed that all extracts have the capacity to decrease the concentrations of lipid hydroperoxides and malondialdehyde, produced in the lipid peroxidation process, in a manner comparable to that of other widely studied antioxidants like melatonin and vitamin E. Moreover, all extracts had the capacity to inhibit the generation of superoxide anion, hydroxyl radical, and the radicals generated by ultraviolet light. When antioxidant activity was calculated, a value was found that was equivalent to a concentration of uric acid between 0.20 and 0.30 mM at the highest concentration of extract used, with uric acid being a potent antioxidant at 1 mM.