Abstract Collagen is a potential corrosion inhibitor for aluminium alloy 2024 (AA2024), being derived from fish scale. FTIR analysis confirms the extraction of collagen. The extracted collagen powder was dissolved within hybrid silica sol-gel forming an environmentally friendly (green) coating. Corrosion behaviour of silica sol-gel (SOL) and collagen/silica sol-gel (CSOL) coated AA2024 in 3.5% NaCl solution was investigated by electrochemical impedance spectroscopy (EIS). In addition, the mechanical properties of both coatings were evaluated using impact test, hardness, micro-hardness resistance, mandrel bend test and cross cut adhesion test. Results showed that collagen improves the corrosion resistance of the coated AA2024, while maintaining the mechanical properties of the silica sol-gel coating.