The relationship between anthropogenic greenhouse gas emissions and climate change is at the center of discussions on mitigating climate change. The share of carbon dioxide emissions derived from fossil fuels in total greenhouse gas emissions shows that it is not possible to evaluate climate change policies in isolation from energy policies. Although there is a consensus on controlling carbon dioxide emissions from fossil fuels and developing carbon neutral energy sources, social, economic and demographic differences between countries make it difficult to transfer the consensus in the scientific field to the political field. The distinction made between developed and developing countries in terms of emission reduction commitments based on “the principle of common but differentiated responsibilities and respective capabilities” in the United Nations Framework Convention on Climate Change signed in 1992 is an important factor in the disagreement in the political arena. This study aims to reveal in what ways the direction of travel and how much the situation of the countries that are members of the G20 has changed between 1990 and 2017, based on per capita income and fossil fuel carbon dioxide emission criteria. For this purpose, using the k-means clustering analysis method, similarities and differences of the member countries have been examined in terms of the mentioned criteria. Although the increase in the total emissions of developing countries is remarkable, when emissions per capita are considered, it can be seen that the difference between developed and developing countries continues to a large extent.