The extrusion-molding device of the invention is for producing a green honeycomb molded body with a cell structure, and the device includes a housing, a screw, a die with slits, a resistance tube and a fragmenting board having through-passages through which a raw material composition passes from the upstream end side to the downstream end side. The through-passages of the fragmenting board have upstream channels composed of a plurality of flow passages extending downstream from the upstream end side, and downstream channels extending up to the downstream end side and having flow passage cross-sectional shapes different from those of the upstream channels.