Abstract: Whether the procuratorial organ is qualified as a proper plaintiff to file environmental public interest litigation has long been a controversial focus in the circle of environmental law.Due to its special legal position and unique supervisory power，the procuratorial organ often exerts dual effects in environmental public interest litigation.Viewing either from the power proper or from juridical status，procuratorial organ’s involvement in environmental public interest litigation is a manifestation of backed force，whose qualification as a subject of litigation comes from public power instead of litigious right in the general sense，therefore it is groundless to grant procuratorial organ the qualification as a plaintiff subject.As environmental litigious right is a kind of procedural right attached to environmental rights and interests，it is necessary to strictly restrict the plaintiff subject of environmental public interest litigation，clearly define procuratorial organ’s role and position so as to fully make use of the public power.

Key words: procuratorial organ；environmental public interest litigation；plaintiff’s subject qualification；subject qualification of litigation, appeal rights