Marzio Nessi (born 1957 in Muralto, Switzerland), is an experimental physicist with a focus on high-energy and high-intensity particle physics.
Nessi studied mathematics and physics at ETH Zurich (Switzerland) where he obtained his Ph.D. degree on an experiment at Lawrence Berkeley National Laboratory. Since 1989, he has been working at CERN. He has been the coordinator of the CERN Neutrino Platform (CENF) and a titular professor in the physics department of the University of Geneva.