Abstract: Abstract: Biomass is a promising, eco-friendly, and renewable source for generating energy, fuels, and bio-chemicals that could partially replace fossil fuels to reduce the pressure of environmental pollution problems. Rice straw is one of the most important lignocellulosic biomass in China, which is a potential feedstock to produce bio-ethanol by enzyme hydrolysis method. The production process of bio-ethanol is composed of three stages, namely pretreatment, enzymatic hydrolysis, and fermentation. The pretreatment process is important step to overcome biomass recalcitrance, and improve the performance of enzymatic hydrolysis. In this study, three types of pretreated method, namely high-temperature hydrogen peroxide pretreatment (HTHP), low-temperature hydrogen peroxide pretreatment (LTHP), and liquid ammonia pretreatment (LAT), were used to overcome biomass recalcitrance and improve the performance of enzymatic hydrolysis. Then, a caparison of the performance of enzymatic hydrolysis and the yield of monosaccharides were carried out by using three pretreatment methods. The contents of monosaccharide (glucose, xylose, and arabinose) of the enzymatic hydrolysate were quantitative determined by high performance liquid chromatography (HPLC). Results showed that three pretreatment methods were effective to enhance the performance of enzymatic hydrolysis, and ordered as LAT > HTHP > LTHP. Based on the chemical component analysis before and after pretreatment, the content of glucan decreased from 35.54% of control sample to 33.76% of HTHP pretreatment, 35.12% of LTHP pretreatment, and 35.86% of LAT pretreatment. The content of xylan decreased from 19.06% of control sample to 14.69% of HTHP pretreatment, 17.53% of LTHP pretreatment, while increase to 19.07% of LAT pretreatment. The optimal pretreatment conditions of HTHP were 120 ℃, mass ratio of 0.75:1 (w/w) between 30% H2O2 solution and biomass ratio, and 60 minutes' residence time. The conversion rates of glucan and xylan were 61.55% and 47.82%, respectively, after 72 hours enzymatic hydrolysis at 1% glucan loading using 15 FPU/(g of glucan) of cellulase. The sugar yield was 334.5 g per kg of rice straw (dry basis) after 144 hours enzymatic hydrolysis. The effect of H2O2 addition on the enzymatic hydrolysis effect was significant, and the excessive addition amount (more than 1.0:1) led to a rapid decrease in the enzymatic hydrolysis rate. The optimal pretreatment conditions of LAT were 90 ℃, mass ratio of 1:1 (w/w) between liquid ammonia and biomass ratio, 60% moisture content (drybasis) and 5 minutes' residence time. The conversion rates of glucan and xylan were 88.62% and 79.29%, respectively, after 72 hours enzymatic hydrolysis at 1% glucan loading using 15 FPU/(g of glucan) of cellulase. The sugar yield was 554.1 g per kg of dry rice straw after 144 hours enzymatic hydrolysis, which is 2.9-fold of producing from untreated straw. The total sugar recovery rate was almost 90%. In conclusion, the performance of LAT pretreatment was more effective than other two pretreatment methods (HTHP and LTHP). This study would be useful to supply scientific and basic data for industrial application of rice straw.