Cellulose nanofibers (CNF) create a physical barrier preventing contact with corrosive substances and improving corrosion prevention. Oil palm fronds (OPF), the primary source of underused biomass waste from plantations, were processed into CNF. The OPF-CNF, mixed with hydroxyethyl cellulose as the matrix, forms a nanocomposite. Corrosion analysis using electrochemical methods demonstrated that copper coated with cellulose-rich nanocomposite containing 5 % CNF had a significantly decreased corrosion rate with an efficiency of 97.92 %. This CNF-based coating, combining barrier and passivation mechanisms, enhances performance, providing a competitive, eco-friendly alternative to conventional coatings.