To obtain a batch type plastic crystallizing device to obtain crystallized pellets for molding such as injection molding, blow molding or the like the pellets before being crystallized of the plastic to be used after being re-crystallized such as a polyester-based polymer compound, a lactic acid-based polymer compound or the like including biodegradable plastics.

This device is equipped with a batch tank 2, a charging port 3 of an anti-solidifying additive and pellets before being crystallized provided at the top end of the batch tank 2, a conical screen separator 5 provided in the bottom part of the batch tank, a space formed underside of the screen separator and an exhaust pipe 8 with an openable shutter 7, through which the crystallized pellets connected to the screen separator is exhausted outside the batch tank, an agitating device consisting of a feeding spiral body 12 for agitating, which rotates in the upper part of the screen separator in the batch tank, or the like, a hot air feeding device 17 for feeding hot air in the above space and the exhaust port 19 of the used hot air provided at the upper part of the batch tank.