Enzymatic pre-hydrolysis using the industrial enzymatic cocktail Cellulyve® was assessed as a first step in a pretreatment process of Miscanthus biomass involving an aqueous-ethanol organosolv treatment. 13 C and 31 P Nuclear Magnetic Resonance and Size Exclusion Chromatography were used to analyze the cellulose and lignin before and after treatment. It was demonstrated that despite a very low impact on the fibre structure (observed by Scanning Electon Microscopy) and composition (in terms of sugars and polyphenolics content), the enzymatic pre-treatement disrupted the lignocellulosic matrix in a considerable extend. This weakening permitted to enhance the removal of lignin during the organosolv pulping and the hydrolysability of the residual cellulosic pulp for the production of monomeric glucose. Using this combined treatment, a delignification yield of 93% and an enzymatic cellulose-to-glucose conversion of 75% were obtained.