Alkaline treatment with sodium hydroxide ( NaOH) is widely used as a pretreatment for enzymatic saccharification of lignocellulosic biomass. For efficient utilization of sugarcane bagasse components, multistep alkaline pretreatment is carried out to extract the useful components before enzymatic saccharification. Alkaline treatment with 1 M NaOH at room temperature led to the extraction of p-Coumaric acid, ferulic acid, hemicellulose and lignin. About 60% of the hemicellulose and lignin was extracted by treatment for 82 h. The residue obtained after 82 h of treatment was further treated with 1 M NaOH at 105 degrees C to produce a residue having less lignin and more cellulose than that obtained by a single 105 degrees C NaOH treatment. The residue obtained after treatment at 105 degrees C was further treated with 1 M NaOH at 170 degrees C to produce a material with 94% cellulose. This phenomenon is probably due to a decrease in the frequency of lignin condensation because multistep treatment has removed part of the lignin from the reaction system. Alkaline treatment at room temperature is effective in accelerating delignification during subsequent alkaline treatments and enables the extraction of aromatic carboxylic acids, arabinoxylan, and lignin without hydrolysis and thermal denaturation.