This paper is to forecast the Korean long-term social discount rate of carbon dioxide (SDRC) and the social cost of carbon dioxide (SCC). It is estimated using the Ramsey function, savings behavior, socio-economic standard, exponential function, expected value and so on. Our findings are as follows. First, the economics of future climate change can be determined using the SDRC. Second, the SDRC declines over time. Finally, forecast shows that the Korean SDRC declines over time and the Korean SCC increases over time.