Today, efforts for alleviating the side effects of global warming and the fact that the environmental pollution is increasing bring about the use of energy sources that cause CO2 emission. Economic growth and economic development that take place in the preceding stages increase the use of energy sources. This process leads to the drain of country’s energy reserves while it also leads to an increase in the levels of CO2. For this reason, variables should be formulated at an optimal level from the perspective of reducing CO2 emissions, saving energy, and adjusting economic performance. In this study, it was studied whether there is a relationship among CO2 emission, energy consumption, and economic growth in G7 countries. For this end, panel unit root tests, panel co-integration tests, and panel causality tests were performed by using the data of G7 countries between 1980 and 2011. According to the unit root test results, the variables that are not stationary at level are co-integrated in the long term. The panel causality test result of the study showed that there is a bilateral causality relationship between CO2 emission and GDP as well as between GDP and energy consumption. For the policy makers, the results of this study prioritises the fact that energy efficiency increases from a technological perspective in G7 countries and that they can make environmental-friendly plans.