As substitute of petrol，bioethanol production from lignocelluloses is one of hot point of research in recent years.A main obstacle of bioethanol production in commercial scale is its cost.One of the most important methods to solve the key problem is raising yield of cellulose hydrolysis by enzyme.However，content and type of lignin in lignocellulosic substrates has a significant effect on the hydrolysis process，as lignin has double actions：as a physical barrier that decreases accessibility of cellulase to cellulose，and as an attractant that adsorbs cellulases i.e.forming non-productive binding.In this paper，structure and adsorption for cellulase of three kinds of ligin，milled wood lignin，Klasson lignin and alkaline lignin were studied，and various surfactants were screened and used for improving enzymatic hydrolysis of lignocelluloses because they have a great impact on cellulase adsorption on lignin.The results showed that there are different structure characteristics for the three kinds of lignin：the highest ability of adsorption for cellulase is Klasson lignin，and then milled wood lignin，the lowest alkaline lignin.The surfactant that can significantly increase enzymatic hydrolysis yield of lignocelluloses is PEG-8000， because it can make cellulase desorption from lignin and reactivation for hydrolysis of cellulose.