This article focuses on the correlation between the secondary objectives of the European Central Bank (ECB) and the right to a healthy environment. Whereas the primary mandate of the ECB is maintaining price stability, the applicable law also envisages secondary objectives, such as supporting economic growth and sustainable development. Crucially, however, there is an emerging scientific literature suggesting a trade-off between economic growth and environmental sustainability. This results in a balancing problem: To what extent environmental protection and sustainability can be balanced with economic growth within the ECB’s monetary policy? This article aims to analyse this issue with a specific focus on legal implications in terms of the right to a healthy environment. This study reveals the failure of the member states to comply with the international obligations under the right to a healthy environment in shaping the law of the ECB.