Research on biomass pretreatment to enhance enzymatic digestibility has been done for more than decades, but a viable continuous pretreatment method needs to be developed. Extrusion has the potential to be a viable continuous pretreatment method. This study investigated the effect of compression ratio (2:1 and 3:1), screw speed (50, 100, and 150 rpm), and barrel temperature (50, 100, and 150 A degrees C) on the sugar recovery from switchgrass (SG) and prairie cord grass (PCG) over a range of moisture contents (15, 25, 35, and 45% wb).The pretreated samples were subjected to enzymatic hydrolysis for sugar recovery measurement. Statistical analyses revealed that a 3:1 screw compression ratio (compared to 2:1) increased glucose recovery by 12% and 8% and combined sugar recovery by 37% and 40% for SG and PCG, respectively. For SG, the highest sugar recovery (45.2%) was obtained at the lowest screw speed (50 rpm) and the highest temperature (150 A degrees C) with moisture content of 15%. The highest glucose, xylose, and combined sugar recovery of 61.4%, 84.3%, and 65.8% were recorded for PCG extruded at a screw speed of 50 rpm and a temperature of 50 A degrees C with a moisture content of 25%. Glycerol and acetic acid were byproducts found in low concentration (0.02-0.18 g/L) for both biomass.