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The present study aimed to characterize melanin pigment extracted from <i>Gluconobacter oxydans</i> FBFS 97. After 14 days of culture at 28 °C in GY (glucose and yeast extract) liquid-state medium, <i>G. oxydans</i> FBFS97 produce the maximum melanin, up to about 12–15 mg/L. The physicochemical characteristics of the extracted melanin showed an ability to dissolve in 1 mol/L NaOH or 1 mol/L KOH, and insolubility in water and most organic solvents, such as chloroform and petroleum ether. The extracted melanin was confirmed to be exact melanin by ultraviolet-visible spectrophotometry, Fourier-transform infrared spectroscopy, thin-layer chromatography, elemental analysis, and scanning electron microscopy. The UV-visible spectrum of <i>G. oxydans</i> FBFS97 exhibited a maximum absorption peak at 230 nm. Extracted melanin demonstrated significant free radical-scavenging activity by DPPH and ABTS methods. The IC₅₀ value of the extracted melanin for scavenging 50% DPPH radicals was 36.94 μg/mL, and the IC₅₀ value of antioxidant activity for ABTS was 4.06 μg/mL. Hence, <i>G. oxydans</i> FBFS97 has the potential to be a new candidate for melanin production.