This study examined the effect of sequential dilute acid hydrolysis and enzyme saccharification conditions of rice husk on hydrogen (H-2) fermentation. The rice husk was hydrolyzed using dilute H2SO4 and then further enzymatically hydrolyzed with various concentrations (0.1, 0.25, 0.5, 0.75, and 1.0 mg protein mL(-1)) of Celluclast 1.5 La. The sequential pretreatment significantly enhanced sugar recovery, up to 174% for 1.0 mg mL(-1) concentration of the enzyme. Increasing the concentration of enzyme slightly increases sugar recovery. While the production of furfural and 5-hydroxymethylfurfural occurred during dilute acid hydrolysis, it was not observed during enzymatic saccharification. At the following H2 fermentation of the hydrolyzates, H-2 yield was improved up to 150% by using the dilute acid and enzymatic hydrolyzate as substrate, as compared when only dilute acid hydrolyzate was used. The highest H-2 yield of 473.1 mL H-2 ri rice husk was achieved with enzyme concentration of 0.75 mg protein mL(-1). (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.