Preventing climate change and preserving biodiversity are two key priorities of the European Union's environmental policy. Paradoxically, the European Union (EU) was not quick to recognise their multidimensional interactions, to the detriment of biodiversity. This means that these two fundamental issues require immediate, coordinated responses, given the urgency and severity of the threats incurred on different space/time scales. This has a significant influence on the solutions offered by society, particularly on the forming and application of laws. Our chapter will focus on EU law, taking into account its essential role for regional integration in these fields. The EU is a key player that holds great responsibility in the environmental crisis that the world is currently facing. Accordingly, the EU has subscribed to various international and internal commitments to meet the crisis. The continued degradation of the environment therefore invites analysis of the reasons for the short- fall, or even inadequacy of EU action. Numerous evaluation reports and studies show the diversity and connected nature of interdependence between climate change and bio- diversity. Have they been integrated into EU law? How? What results were obtained? In law in its current state, the results are inconclusive. Three factors prove this: Firstly, in the wake of the environmental policies that form the overall frame for EU policy in this field, clear strategies for climate change and the conservation of biodiversity6 have been developed.