Gaël Veyssière graduated from Ecole Supérieure des Sciences Economiques et Commerciale (ESSEC), the Paris Institute of Political Studies (Department of Public Service), and holds a bachelor's degree in history from the University of Paris IV.

Before his appointment to Ukraine, he served as Ambassador of the French Republic to the Republic of Croatia from 2019 to 2023. In 2017-2019, he was the Head of Office to the Minister for European Affairs (Ministers Marielle de Sarnes and Nathalie Loiseau) and later the State Secretary for European Affairs (Amélie de Montchalain).

After joining the diplomatic career in 1997, he was twice appointed to the Permanent Representation of France to the European Union, in particular as Press Secretary and Head of the Press Service. He was also Head of the European Union External Relations Department at the Ministry of Foreign Affairs of France.

He also worked as a technical advisor in the office of Prime Minister Jean-Pierre Raffarin, in charge of relations with the European Union, the Balkans and Eastern Europe; as a plenipotentiary to the Director of the Political and Security Department of the Ministry of Foreign Affairs of France; and as a negotiations adviser at the Permanent Mission of France to the United Nations in New York.

Gaëlle Veyssière also served as Deputy Director of the Communication and Press Department of the Ministry of Foreign Affairs of France.

Chevalier of the National Order of Merit.