Provided is a biomass pyrolysis apparatus comprising: a combustion furnace that produces a heat quantity by causing a stable property fuel to combust; a pyrolysis gasification furnace that produces a torrefied material, and a pyrolysis gas by pyrolyzing woody biomass by a heat quantity produced by the combustion furnace; and a pyrolysis gas introduction passage that introduces the pyrolysis gas from the pyrolysis gasification furnace into a boiler, into which the torrefied material is introduced.