In order to improve the utilization of lignocellulose in reeds and reduce the consumption of energy and water and the production of wastewater in the pretreatment process,the technological process conditions and enzymatic hydrolysis effect of twin-screw extrusion coupled with alkali pretreatment of reeds were studied.Firstly,the effects of the twin-screw thread element,screw speed,alkali dosage,treatment temperature and holding time on the enzymatic hydrolysis of reed were investigated,and the changes of the structure and chemical composition of reed fiber before and after different pretreatment were compared.Then,by optimizing the countercurrent washing process of reed after pretreatment,the chemical composition and enzymatic hydrolysis yield of reed were analyzed.Finally,the structure of reed fibers before and after pretreatment was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy.The results show that the twin-screw extrusion under the conditions of 4% KOH treatment at 90℃ for 2 h and a solid-liquid ratio of 1∶8 (m/v) for counter-current washing could effectively damage the reed fibers structure and remove the surface wax,and the lignin removal rate reached 72%.The total sugar yield of the pretreated reeds reaches 0.45 g/g (dry reed) after 48 h of hydrolysis at a low cellulase dosage (10 FPU/g substrate).Twin-screw extrusion coupled with alkali pretreatment of reed can improve the enzymatic hydrolysis efficiency with low energy and water consumption and no wastewater discharge,which provides a low-cost and green feasible technological solution for the utilization of reed biomass.