Abstract: A method of treating a solid lignocellulosic material (10) in which the solid lignocellulosic material (10) is subjected to a treatment, called a mechano-chemical treatment (1), of mixing and chemical degradation of the solid lignocellulosic material (10) so as to form an intermediate composition having a hydrated lignocellulosic material whose enzymatic digestibility is increased relative to the digestibility of the solid lignocellulosic starting material (10), then; the hydrated lignocellulosic material is subjected to a treatment, called a mechano-chemical treatment (2), in which a dispersion is formed, called an aqueous dispersion, of the hydrated lignocellulosic material (10) in an aqueous composition, the aqueous dispersion including at least one enzyme for degrading the hydrated lignocellulosic material (10).