To separate empty bottles into respective sizes without utilizing the vibration.

A plurality of tapered rollers 2 in the state of tilting in the axial direction are disposed in parallel, and the diameters of the tapered rollers 2 are formed finer gradually from the upstream side toward downstream side. A plurality of rollers 3 with steps in the state of tilting in the axial direction are disposed in parallel on the downstream side of the tapered rollers 2. The diameters of upstream sections 3a of the rollers 3 with steps are formed larger than those of the downstream sections 3b, and the rotating direction of the rollers with steps is set reverse to the rotating direction of the tapered rollers 2. Cullets are discharged out of the clearances of the tapered roller 2, and empty container of the small size and middle size are discharged out of the clearances of the roller 3 with steps successively in the above order starting from the upstream side, while empty container of large size are discharged from the downstream side of the roller 3 with steps.