As an important part of energy industry, power grid plays a pivotal and irreplaceable role in promoting low-carbon development. In this paper, the carbon emission reduction potential of power grid corporation was systematically analyzed from qualitative and quantitative perspectives respectively. First, this paper discussed the pathways of power grid corporation’s carbon emissions reduction, including decreasing line loss, promoting clean energy development, and so on. Then, a quantitative evaluation model for carbon emissions reduction potential of power grid corporation was developed. Based on the model, the carbon emission reduction benefits that promoted and achieved by State Grid Corporation of China (SGCC) in 2010 and 2015 were calculated. The results show that the carbon emission reduction benefits of SGCC is 138 million tons in 2010, and will be 481.8 million tons in 2015.