A new system was developed producing hydrogen from cellulose in an ionic liquid using an iridium catalyst under mild reaction conditions. By the employment of an ionic liquid which dissolves cellulose ([BMIM][OAc] (1-butyl-3-methylimizolium acetate), direct hydrogen production from cellulose was accomplished using [Cp*IrCl₂]₂ (Cp* = η⁵-pentamethylcyclopentadienyl) as a homogeneous catalyst. This reaction was performed by a simple procedure using a commercially available catalyst and an ionic liquid. The reaction was also applicable to toilet paper instead of cellulose, thereby indicating that paper waste can be used as a raw material for hydrogen production. The obtained hydrogen was able to be directly used for a chemical transformation (hydrogenation of alkene) and energy transformation into electricity using a fuel cell.