The ligno cellulosic nature of cotton stalk favours to use as renewable material for variety of commercial applications. Present study was evaluating the potential of cotton stalk for bioethanol production. In this regards cotton stalk were subjected to series of treatment including pretreatment, hydrolysis and fermentation. The resultant data shows that physically pre-treated cotton stalk when subjected to 2% alkaline solution at 121^oC for 60 minute followed by enzyme hydrolysis with 100 CMC units of enzyme releases sugar of 0.49 g/g and 24.5 g/L of biomass.Furthermore when it goes to fermentation using co culture of&nbsp;<em>Saccharomyces cerevisiae</em>&nbsp;and&nbsp;<em>Pachysolen tannophilus</em>,givesan ethanol concentration of 9.56 g/L which corresponds to a yield of 0.191 g/g of biomass, 0.298 g/g of holocelluloses and 0.392 g/g of fermentable sugars while fermentation and sugar consumption efficiencies were recorded as 76.85% and 97.81% respectively.