Antioxidants effectively quench oxidative damage to biomolecules. Therefore, antioxidant supplements have emerged as an alternative to reduce oxidative stress-related diseases. Gallic acid shows a wide range of biological activities, including antioxidant properties, but has inappropriate physicochemical properties for wide spread applications. Herein, the chemical structure of gallic acid was modified, and the antioxidative activities of the derivatives were evaluated. The introduction of a 3,4-dihydroxybenzylamino group onto gallic acid via an amide linkage provided an effective antioxidant that showed potent antioxidative activities comparable to those of propyl gallate.