Repeated dose 28-day oral toxicity study in rodents(OECD Test Guidelines 407) is widely used to evaluate the general toxicity of chemicals.In 1998,the Organization for Economic Co-operation and Development(OECD) enhanced existing TG 407 to develop new Test Guidelines for screening and testing potential endocrine disruptors.This procedure has been verified by an extensive international validation program.To provide reference for developing endocrine disruptor evaluation system in China,the enhanced TG 407,its progress and its advantages and disadvantages were summarized in this paper.