This paper describes a novel route for the utilization of algal and lignocellulosic biomass for biofuel production. Dilute sulfuric acid treatment was employed to destroy the rigid algal cells and generate algal hydrolysate. Algal hydrolysate was used as the reaction medium for the enzymatic hydrolysis of lignocellulose from corn stover. The acid treatment parameters were optimized based on the enzymatic efficiency of corn stover digestion and the promotion mechanism is discussed. The algal residues from the acid treatment process were co-digested with corn stover to generate methane. This study showed that algal hydrolysate can be used as a supplemental feedstock and reaction medium to enhance ethanol production. Furthermore, the residues could be utilized as the nitrogen source during the anaerobic digestion of corn stover. (C) 2015 Elsevier Ltd. All rights reserved.