Marc Henneaux studied physics at the University of Brussels in Belgium and received his doctoral degree in 1980 under the supervision of  J. Géhéniau. He was a Visiting Fellow at the University of Princeton for the academic year 1978-1979 and was postdoctoral research associate at the University of Texas from 1981 to 1984. From there, he held a research position at the Belgian Science foundation (FNRS) until 1992, after which he was appointed Associate Professor at the University of Brussels (1993-1996). He has been Full Professor at the University of Brussels since October 1996. Henneaux continues (since May 1998) as the Director of the Service de Physique Théorique et Mathématique at this university.  He has been an Associate Member of CECS since 1985.

Since January 1, 2004, he is also Director of the International Solvay Institutes for Physics and Chemistry, founded by  E. Solvay.

He was awarded the Francqui Prize (Belgium) in the year 2000 and is co-author with Claudio Teitelboim of the book "Quantization of gauge systems" (Princeton University Press, 1992).