Cotton stalk, a widely available and cheap agricultural residue lacking economic alternatives, was subjected to steam explosion in the range 170-200 degrees C for 5 min. Steam explosion at 200 degrees C and 5 min led to significant hemicellulose solubilization (71.90 +/- 0.10%). Alkaline extraction of steam exploded cotton stalk (SECOH) using 3% NaOH at room temperature for 6 h led to 85.07 +/- 1.43% lignin removal with complete hemicellulose solubilization. Besides, this combined pretreatment allowed a high recovery of the cellulosic fraction from the biomass. Enzymatic saccharification was studied between steam exploded cotton stalk (SECS) and SECOH using different cellulase loadings. SECOH gave a maximum of 785.30 +/- 8.28 mg/g reducing sugars with saccharification efficiency of 82.13 +/- 0.72%. Subsequently, fermentation of SECOH hydrolysate containing sugars (68.20 +/- 1.16 g/L) with Saccharomyces cerevisiae produced 23.17 +/- 0.84 g/L ethanol with 0.44 g/g yield. (C) 2016 Elsevier Ltd. All rights reserved.