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Ethanol is an alternative to non-renewable fossil fuels. Ethanol production from lignocellulosic materials provides a low-cost bioconversion system. The agricultural residues, rye straw and bermudagrass that are grown in the Southeast of USA for nitrate and phosphorus removal from swine lagoon effulent have the potential for cost effective ethanol production. Dilute sulfuric acid pretreatment of rye straw and bermudagrass was performed to investigate the conversion of cellulose and hemicellulose to reducing sugars at different pretreatment conditions. The air-dried biomass was pretreated by dilute sulfuric acid with solid loading of 10%, sulfuric acid concentration (0.6, 0.9, 1.2 and 1.5%, w/w) and residence time (30, 60 and 90 min). The amount of total reducing sugars in the prehydrolyzate increased with the increasing acid concentration and residence time. The pretreatment time of 30 min with different acid concentrations at 121C was not longer enough for the sufficient solubilization of hemicellulose in the biomass. When the acid concentration was up to 1.2%, the reducing sugars produced after 60 min and 90 min pretreatment didnt show significant difference. The solid residues were hydrolyzed by excessive cellulase to investigate the enzymatic digestibility. Cellulose in the pretreated feedstock was highly digestible by cellulase from Trichoderma reesei. The maximum reducing sugars produced after acid pretreatment and saccharification were about 500 and 650 mg/g biomass for rye straw and bermudagrass, respectively. The acid pretreatment was more effective for the total reducing sugar yields from bermudagrass than from rye straw.