PURPOSE: To produce a green strip having a high density and strength by winding belts on rolls disposed apart from each other at a prescribed space to constitute a pair of endless tracks and rolling powder in the rolling space formed between the endless tracks.

CONSTITUTION: The plural rolling rolls 10, 11 are provided between driving rolls 6, 7 and driven rolls 8, 9 which are parted from each other at required spaces. The belts 12 such as steel belts are wound thereon to constitute a pair of the endless tracks. A pair of the endless tracks are opposed in a perpendicular direction to form the rolling space of narrower toward the lower side from the upper side therebetween. The belts 12, 13 are driven in the above-mentioned constitution and the powder 4 of metal, etc., in the upper hopper 3 is withdrawn between the belts 12 and 13 and is rolled by the rolling rolls 10, 11. The rolled metal is taken out via side seals 16. The thickness of the green strip 5 is adjusted by rolling down adjusting devices 14, 15 at this time. The green strip 5 having a large width is thereby formed.