Cellulose is one of the most abundant biopolymers in the world. Still, chemical modifications are required to obtain superior mechanical properties when combined with other polymers such as poly(lactic acid) (PLA). The use as a reinforcement in biocomposites is limited due to the hygroscopic behavior and low interfacial interactions with matrix polymers which need to be overcome. This work deals with the coupling of poly(lactic acid) (PLA) with maleic anhydride (MA) and the incorporation of extracted cellulose from sawdust biomass through the extrusion process. As a previous study, structural and thermal characterization is performed to determine the properties that will permit the achievement of a biobased product in the future. The present results will serve to start migrating into biobased products and to reduce the use of fossil-raw materials in the plastic field.