For environmental sustainability, lignocellulose is substituted for crops as a renewable source for biofuel production. Because of the network of intra-and intermolecular hydrogen bond in the crystalline structure of cellulose, the rigid structure of cellulose is difficult to convert into sugars under mild conditions. Therefore, the efficient process of destroying the recalcitrant structure of biomass is the core technology for the conversion of biomass into sugars. The novel technique of lignocellulose hydrolysis in ionic solution, which comprises ZnCl2 and formic acid, is investigated. In this ionic solution, biomass can be efficiently dissolved and hydrolyzed into reducing sugars, with a nearly 96% yield of reducing sugar from cellulose and a 90-100% yield of reducing sugar from crude biomass. Through 7 extraction stages, formic acid and ZnCl2 was extracted by tributyl phosphate from the ionic solution with the separation rate of 99.8 and 95.5%. These results show that this ionic solution is an effective medium for lignocellulose hydrolysis and can be recovered by liquid-liquid extraction. All experiment conditions can be used accordingly to develop a new hydrolysis technique for cellulosic sugar production.