Abstract Melanin was isolated from a plant source (black garlic: BG) and characterized and compared with melanin obtained from an animal source (sepia ink: SI). SEM observations showed that both melanins were spherical with the diameter of 100–1200 nm and 100–200 nm for BG and SI melanin, respectively. Fourier transform infrared (FTIR) test result showed characteristic absorption peaks for melanin emerged at near 3440 cm−1 and 1630 cm−1. The melanins showed a high UV absorption capacity at the range of 210–250 nm. Both melanins were highly heat-stable, however, the SI melanin was more heat stable than the BG melanin. Also, both melanins had high antioxidant activity with a strong DPPH free radical scavenging ability. As a new source of melanin for substituting the sepia melanin, the melanin isolated from BG could be used as a food additive, food packaging, and biomedical applications.