[en] With the recent United Nations Climate Change Conference (COP21) in Paris, a great deal of attention is being given to low-carbon energy technologies and policies that could help the world limit the global temperature increase to 2 deg. Celsius. Among these technologies, nuclear energy, which remains the largest source of low-carbon electricity in OECD countries and the second largest source of electricity at the global level after hydropower, can play a key role. The 2011 Fukushima Daiichi accident heightened public concern over the safety of nuclear energy in many countries. Because of the potentially far-reaching consequences of the use of nuclear energy on the environment in the case of an accident, it is commonly thought that nuclear law and environmental law are not entirely compatible or do not necessarily share the same objectives. Nuclear law may be defined as 'the body of special legal norms created to regulate the conduct of legal or natural persons engaged in activities related to fissionable materials, ionizing radiation and exposure to natural sources of radiation', while environmental law can be defined as 'the body of law that contains elements to control the human impact on the Earth and on public health'. These two areas of law were considered independently in the past, since the initial focus of nuclear law, which was developed before environmental law, was to protect people and property, without explicitly referring to the environment. However, the 1986 Chernobyl accident and increasing environmental concerns during that same decade led to a growing emphasis on environmental protection in the field of nuclear activities. On the one hand, nuclear law, as 'lex specialis', aims to ensure that nuclear activities are carried out in a manner that is safe for both the public and the environment. On the other hand, the expansion of the realm of environmental law has given rise to the application of environmentally focused international instruments to those same nuclear activities. This article illustrates the growing interrelationship between these two areas of law. Remarkable advances have been made over the past thirty years to take into account international environmental law principles and instruments in the field of nuclear law. Parties to international instruments dedicated to the field of nuclear activities have increasingly recognised the necessity to set high targets in relation to environmental protection. In parallel, international environmental law conventions have extended their reach to all major nuclear activities for peaceful purposes. The strong interrelationship between environmental law and nuclear law results in a complementary framework, where one body of law covers the weaknesses of the other. It can be reasonably expected that this trend will continue in the future