We have studied the change in composition for three bamboo species of different ages with sulfite pretreatment and treatment with dilute sulfuric acid. Enzymatic hydrolysis and ethanol fermentation of the hydrolyzate were carried out (sequentially and simultaneously). We show that sulfite pretreatment significantly increases the conversion of cellulose to glucose during enzymatic hydrolysis, and the conversion depends on the type and age of the bamboo. When 2-year moso bamboo is treated at a temperature of 180 °C for 30 minutes with a solution containing 5 % sulfuric acid and 9 % sodium sulfite, conversion of cellulose to glucose during hydrolysis is as high as 89.3 %. A higher ethanol yield results from sequential separate hydrolysis and fermentation than for simultaneous saccharification (hydrolysis) of cellulose and fermentation.