The theory of environmental right, the theory of public trust and the theory of private attorney general guide the direction of expanding the subject qualification of environmental public interest litigation. The development of the system of subject qualification of environmental public interest litigation in foreign countries presents the basic strategy of coexistence of expanding and restraining. The current environmental public interest litigation system in China has such problems as the absence of the qualification of the citizen plaintiff, the lack of vitality of the qualification of the environmental organization plaintiff, the ambiguity of the qualification of the administrative organ plaintiff and the clear but imperfect qualification of the inspection organ plaintiff, which make it difficult to give full play to the actual effect of the system. China should gradually expand the plaintiff of environmental public interest litigation subject qualification, establish the plaintiff’s subject qualification system of pluralistic coordination and cogovernance with environmental protection organizations and ecological environment administrative organs as the main body, procuratorial organs as the auxiliary, and citizens’ direct prosecution as the supplement, and set up necessary supporting measures to prevent the negative effects caused by the too wide scope of subject qualification. 