The present disclosure is related to a method for increasing the ethanol concentration from the conversion of lignocellulose. The pretreated solid residues are mixed with ethanol-containing broth from the fermentation of xylose hydrolysate by Pichia stipitis and then are performed under the process of simultaneous saccharification and fermentation (SSF) with Sacharomyces cerevisiae and cellulase for converting cellulose to ethanol. The final ethanol concentration in broth as well as the ethanol productivity is increased at least 1.8 times in comparison of conventional process for lignocellulosic ethanol production.