waste pastry was hydrolyzed by glucoamylase and protease which were obtained from solid state fermentation of aspergillus awamori and aspergillus oryzae to produce waste pastry hydrolysate. then the effects of hydraulic retention time on hydrogen production rate in the suspended microbial growth system from waste hydrolysate were investigated.The maximum HPRs of CSTR and CMISR were obtained at HRT of 6 hour and 4 hour,respectively.The first-order reaction could be to describe the undigested waste pasty and consumed 77.2% for carbon content of the waste pastry remained 22.8% in the undigested waste and consumed 77.2% for carbon dioxide and soluble microbial products.To our knowledge,this is the first study which reports biohydrogen production from waste pastry