Biorefinery technology is a current alternative to petroleum based industry to produce energy, chemicals and materials. The use of forest and agricultural lignocellulosic residues as raw materials to generate value-added products has become a topic of great interestdue to their renewability and availability. Pine sawdust is a promising candidate as raw material for biorefinery. This waste, which comes from the primary industrialization of wood, is available in large quantities, at low cost, and is currently open-airburned. The aim of this study was to obtain cellulose nanofiber (CNF) from pine sawdust. Delignification methods were applied to pulp until a kappa number lower than 1was achieved. CNF was produced by the combination of chemical (TEMPO-oxidation) pretreatment and mechanical destructuration in a homogenizer. Once CNF was produced at different oxidation degrees, the degree of polymerization, cationic demand, carboxyl rate, and the yield of fibrillation were determined with the purpose of assessing the effect of the oxidation degree on the final properties thereof.Finally, the suitability of using the obtained CNF as paper strength additive was studied through the assessment of the mechanical properties increase of paper