Arnaud Leroy began his career at the European Commission within the Department for Maritime Affairs after studying Maritime Law and International Law of the Sea at the Faculty of Nantes, France. Subsequently, he was parliamentary assistant of Gérard Onesta, vice president of the European Parliament. In 2004, he joined the European Maritime Safety Agency (EMSA), where he was responsible for the protection of the marine environment and issues related to climate change.
Deputy of the French citizens living outside of France since 2012, Arnaud Leroy is a member of the Commission for Sustainable Development and Spatial Planning of the National Assembly and President of the study group on climate change. He is also full member of the National Observatory guidance council on the effects of global warming in France and in the departments and territories oversees. He is the author of a bill regarding the blue economy filed in July 2015 and promulgated on 21 June 2016.