Abstract: China is the largest copper consumption country around the world.Combining with history and trends of China's refined copper industry development,with the help of the model of social welfare,refined copper reserves in China has been carried on the quantitative analysis,the optimal size of China's refined copper reserves calculated for 82.6days of consumption and 268 million tons in 2015;According to the sensitivity analysis,the main factors that affect the optimal reserves are the coefficient of the elasticity of demand and the size of average interruption;Combining with the reserves utility maximization function,selecting different scenes,obtained under different scenarios eventually China's refined copper optimal reserves,it is concluded that China's optimal refined copper reserves should be between 75~ 85 days of consumption,244～276million tons in 2015.