To provide a device for triboelectrifying plastic by which several kinds of crushed plastic chips can be triboelectrified with sufficient charge quantity and then can precisely be separated, and to provide a plastic sorting apparatus using the device.

The device for triboelectrifying several kinds of the crushed plastic chips is provided with a casing 22 arranged in the horizontal direction and having a supply part 21 for the plastic chips, which is formed on the upstream side, and a discharge part 23 of the plastic chips, which is formed on the downstream side, and a rotary screw 27 stirring, which is arranged freely rotatably in the casing 22 and triboelectrifies the plastic chips by stirring. The casing 22 is formed of a tubular body whose cross section of inside wall is regular hexahedron.