This study investigates the relationship between economic growth, final consumption, investment, energy use and CO² emissions in two groups of Middle East and North Africa (MENA) countries: Oil Poor Countries (OPC) and Oil Rich Countries (ORC). It is assumed and verified that the structural relationship between GDP growth, energy use and CO² emissions is different in these two groups of countries. FGLS panel estimations were carried out over the period 1974–2014. In ORC, no significant relationships are observed between energy use and GDP, whereas CO² emissions and GDP are positively linked. In OPC, there are opposite connections: a positive link between GDP and energy use, whereas the impact of CO² emissions on GDP tends to be negative. In both groups of countries, a positive and bi-directional link is observed between energy use and CO² emissions. The strength of this link is twice bigger in OPC than in ORC. This indicates that CO2 reduction policies conducted through energy use control (quantitative and qualitative) will have higher effect in OPC than in ORC. This also shows that the relationships between economic growth, energy use and CO² emissions differ noticeably and structurally between OPC and ORC. These results provide new insights into the opportunities and threats faced by CO2 reduction policies in OPCs and ORCs.