This article sheds light on a concept little known to public health actors in France: regulatory science, used to describe the range of scientific activities used to produce the knowledge mobilized to support, develop or adapt public policy decisions. The objective is to understand how the expression appeared in the mid-1980s and was formalized into a sociological concept by the American writer Sheila Jasanoff in 1990, and has gradually imposed itself in American, Japanese and European regulatory agencies as a new scientific discipline. The article examines the evolution of the concept and the various approaches proposed to define regulatory science. It highlights its hybrid and heterogeneous nature, underlining the different characteristics that the expression covers according to the institution which formulates it (FDA, EMA, PMDA) and the scope of application that it covers. Based on concrete examples of the application of regulatory science practices in three broad areas of health risk, the paper focuses on the role of research in the decision-making process by showing how the emergence of new methods designed to strengthen the regulatory capacities of regulators and the role of academic communities associated with this approach, contribute to the strengthening of public health policies in France and worldwide.