Increase of the greenhouse gases emissions during last century has led remarkable changes in our environmentunderstand these changes around us. The concentrations of greenhouse gases (CO2, CH4, N2O, CFCs) have beencontinuously measured at Global Climate Change Monitoring station in Gosan, Jeju since January, 2002. In thisstudy, the variation characteristics of greenhouse gases as well as their annual, seasonal and diurnal trend using thedated with the methods recommended by WDCGG(World Data Center for Greenhouse Gases). The concentrationof CO2 was increasing continuously by 2.1 ppm/year, while CH4 did not show any increasing or decreasing trendclearly for 4 years. The concentration of N2O was slightly increasing and CFCs were decreasing except CFC-12to be consistent with the global trend. But the concentration level of CO2 in Korea was more or less higher than abroad.