This study demonstrates sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) for robust bioconversion of corn stalks. With only about 3% sodium bisulfite charge on corn stalks and 30 min pretreatment at temperature 180°C, SPORL can achieve near complete cellulose conversion to glucose in 48h enzymatic hydrolysis. Sulfuric acid charge has great effect on SPORL pretreatment. Enzymatic cellulose conversion of substrate increased with the increase in acid charge under the studied conditions. Bisulfite with different counter-ions can be used in the SPORL. Magnesium as counter ion was found to be more effective on enzymatic hydrolysis of substrate than sodium or ammonium.