A promising fungal pretreatment method was developed for enhancing hydrogen production via thermophilic fermentation of raw cornstalk mixed with the pretreated cornstalk by Trichoderma reesei Rut C-30. In comparison with mesophilic hydrogen fermentation at 35 degrees C, thermophilic hydrogen fermentation at 55 degrees C gave higher hydrogen production from the mixed cornstalk because higher cellulase activity under thermophilic condition was favorable to lignocellulose hydrolysis. When the pretreated cornstalk was mixed with the raw cornstalk at an optimal blending ratio of 1:5, the cumulative hydrogen volume reached the maximum level of 194.9 mL, which was 209% of that obtained in direct fermentation of raw cornstalk. The present results indicated that the fungal pretreatment had a great potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable hydrogen energy. (C) 2011 Elsevier Ltd. All rights reserved.