Five agro-residues namely sugarcane bagasse, sugarcane tops, sugarcane trash, corn husk and corn stover were subjected for various methods of pretreatments with particle sizes of 0.5 mm, 1.0 mm and 10.0 mm. The treatment combination of 3.0% NaOH coupled with 1210C temperature with particle size 0.5 mm was found to the best for the recovery of both cellulose and hemicelluloses after pretreatment in sugarcane bagasse (0.813 g g-1), sugarcane tops (0.786 g g-1), sugarcane trash (0.806 g g-1), corn husk (0.806 g g-1), and corn stover (0.806 g g-1). The treatment of 1% H2SO4 plus autohydrolysis at 2000C decreased the hemicellulose content significantly and also resulted in maximum loss of lignin contents in sugarcane bagasse, sugarcane tops, sugarcane trash, corn husk and corn stover by 80.71, 78.98, 70.63, 71.43 and 73.80 per cent respectively in particles of size 0.5 mm.