High pressure processing (HPP) is an emerging technology for food preservation, however its application in pretreatment of lignocellulosic biomass has not been studied; therefore, the objective of this work was to evaluate the effect of HPP in combination with sodium hydroxide on the enzymatic hydrolysis of sugarcane raw and prehydrolyzed bagasse. The results indicated that high pressure treatments alone or combined with sodium hydroxide had a little effect on the lignocellulosic fraction of sugarcane bagasse, however in prehydrolyzed bagasse, removal of the major hemicellulose was observed. Also, changes in the microstructure and crystallinity of sugarcane bagasse were observed at 450 MPa as the modification of the cellulose fiber improved the porosity, increasing the susceptibility of bagasse to cellulases, obtaining a glucose concentration of 25.91 g/L with NaOH (6% treatment). These results are important because the application of HPP on lignocellulosic materials could be used to get fermentable sugars for production of food additives.