This study investigates the combination of acidic and alkaline for pretreatment to enhance the efficiency of cellulose enrichment for a lignocellulosic material, herein, rubber sawdust. Treating the material with acid followed by alkaline treatment resulted in higher efficiency, leading to an increased hydrolysability of the material in Simultaneous Saccharification and Fermentation (SSF) Processes. The pretreatment of rubber sawdust with an H2SO4 1.0 wt% solution for 5.5 h, followed by NaOH 2.75 wt% solution for 24 h, gave the best response to a factorial experimental design. Under these conditions, the efficiency was 69.25 %with a cellulose crystallinity index of 50.31 %. The SSF conversion of different pretreated materials to bioethanol also confirmed that increasing the amorphous cellulose content led to higher efficiencies.