A graduate of the Bordeaux Institute of Political Studies, Rémi Castets studied Chinese (Master's degree) at the National Institute of Oriental Languages and Civilisations (INALCO). He then obtained a DEA (postgraduate diploma) in comparative analysis of political areas (specialising in Asia) and a PhD in political science from Sciences Po (Paris Institute of Political Studies).

He conducted part of his Chinese studies and research in the People's Republic of China at Nanjing University (1998-1999), Xi'an Jiaotong University (2001-2002) and the French Centre for Contemporary Chinese Studies in Hong Kong between 2004 and 2006.

He teaches in the Department of Chinese Studies at Bordeaux Montaigne University (UBM). Director of the Chinese Studies Department at UBM between 2016 and 2020, he was an associate researcher at CERI (Sciences Po Paris) and the Central Asian Programme (The George Washington University) and currently co-directs the Joint University Research Unit (UMRU) 24140 Asian Dynamics, Interactions and Interculturality (D2iA) (Bordeaux Montaigne University, La Rochelle University). He is also a full member of the National Council of Universities and a member of the Scientific Council of GIS Asie. His research focuses mainly on the relationship between Islam and politics in China, the Uyghur question and the Belt and Road Initiative.