This invention presents a valorization process of Scomberomorus commerson (mackerel) waste into bio-oil through slow pyrolysis using a fixed-bed reactor operated at 340–360°C with LPG heating. The process converts fish waste into a hydrocarbon-rich liquid that can serve as a precursor for bioaviation fuel, offering a sustainable solution for both waste management and renewable energy production. The produced bio-oil was characterized for density (880 kg/m³), viscosity (3.02 mm²/s), and heating.