Jean Fréchet was born in France and received his first university degree at the Institut de Chimie et Physique Industrielles (now CPE) in Lyon, France, before coming to the US for graduate studies in organic and polymer chemistry at the State University of New York, College of Forestry, and at Syracuse University. He joined the Chemistry Faculty at the University of Ottawa in Canada in 1973 and remained there until 1987 when he became IBM Professor of Polymer Chemistry at Cornell University. In 1995 he was named to the Peter J. Debye Chair of Chemistry at Cornell University. In 1997, Jean Fréchet joined the Chemistry Faculty at the University of California, Berkeley and was named the Henry Rapoport Chair of Organic Chemistry in 2003 and Professor of Chemical Engineering in 2005.

In addition he is a principal investigator in the Materials Science Division of the Lawrence Berkeley National Laboratory, and is Director of the Organic and Macromolecular Facility for the Molecular Foundry, Lawrence Berkeley National Laboratory. He has authored over 700 scientific papers and holds over 70 United States patents. His research at the interface of organic and polymer chemistry is in the broad area of nanoscience and nanotechnology, and is directed towards functional macromolecules, their design, synthesis, and applications. Current topics include new synthetic approaches to macromolecules with controlled architecture, engineered polymer systems and molecular machines; the design, synthesis, and applications of dendritic and other functional polymers; novel imaging materials for nanoscale lithography, energy harvesting and conversion; catalysis with dendritic macromolecules as enzyme mimics; polymers in separation and molecular recognition; and functional macromolecules in targeted drug delivery and immunotherapy.