A coal gasification furnace is provided which yields a hydrogen-rich gas through coal gasification to render the miniaturization of shift reactors possible. The coal gasification furnace (G) into which a gasifiable material such as coal and a gasifying agent have been introduced yields a coal gasification gas through gasification reactions proceeding therein. At least one of water and steam is introduced into the furnace as a substance for accelerating hydrogen formation reactions proceeding simultaneously with the gasification reactions.
