Abstract: This invention relates to a fireproof container with improved circulation of heat and safer use. According to an embodiment of this invention, a fireproof container, to be loaded in an industrial furnace to perform a thermal treatment of a powder or a target, includes a prominent member formed on the outer walls thereof Also, according to another embodiment of this invention, a fireproof container for use in thermal treatments has a hexahedral shape with a space having a predetermined volume in which a powder or a target to be thermally treated is placed, and includes a protrusion block having a predetermined shape formed on at least one of the external front surface, rear surface, left side surface, and right side surface of the fireproof container.