To provide a plastic material sorting apparatus capable of sorting plastic pieces accompanying recycling by kind with high accuracy.

A quantitative supply apparatus 5 supplying plastic pieces 2 to a metal drum electrode 6 is constituted of a quantitative supply container 21 for supplying frictionally charged plastic pieces 2 quantitatively, the plate- shaped supply tray 22 arranged between the quantitative supply container 21 and the metal drum electrode 6 so as to be downwardly inclined at a predetermined angle and guiding the plastic pieces 2 supplied from the quantitative supply container 21 to the metal drum electrode 6, a vibration device 23 for vibrating the supply tray 22 and the partition member 32 arranged above the supply tray 22 and forming a gap 31 with predetermined height along with the surface of the supply tray 22.