The soaring energy consumption in the world, restriction of fossil fuels sources, and also environmental impacts make bioethanol the most popular alternative energy source in recent years. Ethanol could derive from different kind of raw materials such as sugar-based, starched-based, and lignocellulosic materials. Rice husk as an agricultural residue can potentially be employed for production of ethanol. In this work, the rice husk which was utilized for production of ethanol contains 32.2% wt cellulose, 15.0% wt hemicelluloses, and 18.9% wt lignin. Pretreatment is an important step in order to enhance the yield of ethanol production from lignocelluloses through removing lignin, increasing the access of enzymes to the cellulose, and reducing the cellulose crystallinity. Alkali pretreatment with sodium hydroxide and sodium carbonate solution with concentrations of 1 and 2M was performed at the temperatures of 50 and 100°C for 30°C and 105 min. To investigate the effect of the pretreatments, enzymatic hydrolysis process on untreated and pretreated samples were done at 45°C for 72h by loading 30 FPU cellulose (Celluclast 1.5 L, Novozyme, Denmark) and 60 IU ?-glucosidase (Novozyme 188, ovozyme, Denmark) er grams of dry ubstrates. The est result of hydrolysis yield was 49.9%, which was related to pretreated substrate using 2M sodium hydroxide solution at 100°C and for 105 minutes. Furthermore, simultaneous saccharification and fermentation was performed under anaerobic conditions at 37°C for 72h. The pretreatment could increase the ethanol yield from 15.1% to 72%. In the next step, statistically based experimental designs were applied to optimize the pretreatment condition. The combine effects of time, temperature and sodium hydroxide concentration were studied using a central composite design. The optimal values of variables for maximum ethanol production were as following: 2.6M sodium hydroxide concentration, 67°C, and 150 minute and the ethanol yield under the condition was 86.7%. Furthermore, the comparison between the performance of Saccharomayces cervisiae and Mucor hiemalis during the simultaneous saccharification and fermentation was done. The results of the yield of ethanol produced by S.cervisiae and M.hiemalis indicated that the fungus had a better ethanol yield. Beside ethanol, biomass is the value added byproduct of ethanol production performed by zygomycetes fungi. The iomass of the zygomycetes fungi contains appreciable amounts of chitosan, which is a biodegradable polymer with numerous applications especially in food for instance food preservation and pharmaceutical industries such as carriers in DNA and drug delivery systems and arti?cial skin bases. Lipid is the other by-product of ethanol production from zygomycetes. Lipids from filamentous fungi contain essential fatty acids such as Gamma-linolenic acid which is known for both its pharmaceutical and nutraceutical applications. In this study the M.hiemalis biomass was analyzed and the amount of each component of biomass were reported. The amount of protein was 0.37g /g biomass and for alkali insoluble material in the biomass was 0.63g/g dried biomass which was consists of 0.21g phosphate, 0.41g Glucoseamine and 0.05g N-acetyl Glucoseamin. Moreover, the lipid content of the biomass was measured 16.2% (based on dry biomass), by using the methanol: toluene (1:1) solvent for oil extraction. K e y Words Ethanol, Pretreatment, Sodium hydroxide, Rice husk, M.hiemalis , Chitosan, Lipid.