To enhance a recovering efficiency by comminuting plastic container body after previously separating unnecessary parts such as a neck part and a label by a separator.

Containers of vinyl chloride are manually classified and removed. And, plastic bottles are thrown in a separator, and neck parts and labels are removed from the bodies (S1). The bodies are classified from the treated materials, and unnecessary parts such as the labels are contained in a residual container (S2). The classified bodies are comminuted to chip-like state (S6), cleaned and dried (S7). Thereafter, metallic impurities are removed by utilizing a magnet or a metal detector (S8). Then, chip-like comminuted materials are classified in response to particle sizes (S9). Here, the materials of desired particle size are pelletized to pellet-like state (S10). The comminuted materials of desired particle size or less are contained in a residual container as unnecessary material, and the comminuted materials of desired particle size or more are again comminuted (S6).