Jiangsu Province is one of the main pig producing areas in China, and pig farming is developing towards large scale. The relationship between the scale of pig farming and economic benefits is of great significance for guiding pig farming in Jiangsu Province. Based on four different scales of pig farming in Jiangsu Province, the cost and profit margin of pig farming from 2002 to 2016 was analyzed in the paper. It was concluded that the economic benefit of medium-scale pig farming was the best. On this basis, the comprehensive benefits of different pig farming scales in Jiangsu Province were further measured by using the grey situation decision method. The results showed that the economic benefit of medium-scale pig farming was higher in Jiangsu Province. Then from the perspective of establishing and perfecting the financial system, promoting the operation and development mode of‘company +farmer +cooperative’, protecting the ecological environment and strengthening the prevention and control of epidemic situation, some suggestions were put forward to promoting the medium-scale development of pig farming.