The safety of surface water is an important factor concerning the health of our citizen and sustained development of society and economy in China and need to be paid great attention. Risk assessment of heavy metal pollution in surface water is a new assessment method which quantitatively connects water heavy metal pollution with human health. This paper established a risk assessment model of heavy metal pollution of surface water environment on the basis of achievements in risk assessment research at home and abroad. By use of the measared data from Dadu river at Sangu village of Hanyuan county, Ya'an city, it carried out the risk assessment of heavy metal pollution of water environment, and studied the problems of health risk of heavy metal pollution of surface water environment. The results will provide important basis for the risk management and decision-making of surface water and reference for the risk assessment of heavy metal pollution of surface water environment.