This paper presents the study of combinated pretreament and enzymatic hydrolysis of Acacia mangium and Eucalyptus urophylla wastes for ethanol production. The basic chemical composition of the wood and wood wastes (content of cellulose, lignin, pentosane and other components) were determined. Eucalyptus wood have the cellulose content of 46.4 percent, lignin of 25.3 percent and pentosane of 19.6 percent. Cellulose and lignin content of acacia higher, respectively 49.6 percent and 26.8 percent. Same content of wood wastes are lower than wood. Studies the influence of mechanical (refining), chemical (water and sodium hydroxide) pretreament to enzymatic hydrolysis of wastes were performed. Water pretreatment of wastes fraction less 0,2 mm given yield of reduce sugars higher than other fractions. The water pretreatment at nonnal or high temperature have very low influencing to enzymatic hydrolysis. Enzymatic saccharification of non-treated or water treated wood wastes (both type of wood with fractions less 0.2 mm) at 30°C or 100°C for 1-4 hours, only given yield of reduce sugars at 10 - 11 percent of absolute dry (AD) wood. However wastes fraction less 0.2 mm was the optimal size for enzymatic hydrolysis. While in the same treatment conditions (at temperature of 100'C, liquor ratio of 1:50, time of treatment was 1 hour) with sodium hydperoxide concentration of 1 percent, the yield of reduce sugars was higher. But the sodium hydroxide pretreatment of wastes by solution with NaOH concentration less 1 percent at a temperature of 30-100°C for 1-4 hours was less efficiently, yield of reduce sugars performanced less than 15 percent of AD wastes. In case of pretreatment by 1-5 percent NaOH solutions, yield of reduce sugars was about 24-38 percent according to cellulose conversion of 54-88 percent.