Abstract: Environmental cost, as an important indicator of environmental pollution degree, is the monetization of environmental impact. Based on agricultural environmental cost evaluation method and emission coefficient method, using the data of hog scale production in Hunan Province, this paper established an environmental cost assessment model of hog scale production, from two aspects of quantity and value of the pollutant, to evaluate the environmental impact of hog scale production in Hunan Province. Results showed that the annual environmental cost of pollution from hog scale production was 2 520 million yuan in Hunan Province in 2010-2014, inlcuidng the treatment costs for water pollution, air pollution, soil pollution, and heavy metal pollution. The annual growth trend was steady. Due to the differences of hog scale production and farmland in counties, there are big differences of the degrees of pollution among different regions, with a trend of increasing pollutant emission in the production concentration areas. To help control the environmental cost of hog scale production, this paper suggests: to establish cost sharing mechanism, to enhance the cognitive level of farmers on environmental pollution of hog production from different channels, and to improve the rural financial supply mechanism for farmers to broaden the financing channels.