Greenhouse gas emissions are considered as the main cause of climate change. Investigation of economic dimensions of greenhouse gas emissions and its environmental effects especially in a situation where the volume of greenhouse gas increasingly is rising is very important. In this paper, the relationship between greenhouse gas emissions i.e. carbon dioxide and GDP per capita and energy consumption in Iran during the years 1370 to 1387 using the Environmental Kuznets Curve has been studied. Due to the fact that in this study the relationship between the dependent and independent variables is equivocal Fuzzy regression models were used to estimate this relationship. Fuzzy regression estimates an interval of possible values for the output variable while the classical regression calculates a value for the output variable. Results from the fuzzy regression model show an incomplete Kuznets model in Iran. The results of the maximum and minimum amount of carbon dioxide emissions in 1387 are approximately 269,000 and 204000 kt respectively. Knowledge about the relationship between energy consumption and carbon dioxide emissions can be substantial in the overall energy sector planning policies, provide useful guidance.