Abstract: Monitoring environmental risk sources scientifically was the most effective way for the prevention of environmental pollution accidents. However, the sites setting method of environmental risk sources monitoring had not been formed systematically in China. Referencing to the concept of basin water-quality target management, the monitoring sites setting methods for major liquid environmental risk sources in chemical industry parks were constructed based on the principle of “by region, by type and by grade”. General requirements on monitoring regions for the different grades of major liquid environmental risk sources were proposed, and the methods and regulations for monitoring sites setting for major liquid environmental risk sources in different regions were also put forward. One chemical industry park was analyzed for demonstration of monitoring sites setting.