PURPOSE: To improve granulation effects by providing a flange to cover a part for extruding pellet on the outer periphery in such a manner that said flange protrudes from said periphery, and by forming a moulding hole formed on the outer circumferential wall so that said hole consists of a specially dimensioned tapered press-in portion and a small through hole portion which extends from said tapered portion.

CONSTITUTION: Outer circumferential wall portions of a pair of rotatable cylindrical dies 5 having a plurality of moulding holes 7 on their outer circumferential walls 5b are caused to contact with each other so that raw material fed into between the cylindrical die 5 is forced into the holes 7 to extrude pellets. And a flange 8 is provided on the outer circumferential periphery so as to cover the pellet extruding portion, protruding from said periphery. The moulding hole 7 is composed of a tapered press-in portion 7a having predetermined dimensions and a small through portion 7b extending from said tapered portion 7a, wherein it is arranged that D/d=1.1W1.7, e/d=1W6, where D: diameter of press-in portion 7a, d: diameter of through portion 7b, e: length of through portion 7b. Consequently, granulation effects can be raised.