Stéphane Horel is a French journalist and documentary filmmaker born in 1976. A contributor to Le Monde, she has conducted several investigations into conflicts of interest and lobbies.

A graduate of the Centre de formation des journalistes (CFJ) in 1999, she worked in various editorial offices of the written press (Le Monde, AOC, Le Vrai Papier Journal, Le Canard enchaîné) and for television channels (Arte, France 5) before devoting most of her time to independent investigations.

An investigative journalist, she writes in particular about the influence of private interests on the general interest, conflicts of interest and lobbying. According to her, "lobbies have become essential players in democratic life despite any electoral legitimacy".

She shows that the European Commission sometimes copies texts written by lobbies. Regulatory actors believe themselves to be immune to lobbying and attempts to influence industrialists, who in turn play on their naivety.

Her work on lobbying by the chemical and pesticide industry on European projects to regulate endocrine disruptors has earned her a certain notoriety; she notably received a Laurel from the Columbia Journalism Review for an investigation into the conflicts of interest of 19 scientists who had attacked this regulatory project, as well as the Louise Weiss Prize for European journalism in 2015 for her work on the subject. She has also regularly collaborated with the Corporate Europe Observatory, an action-research association on industrial lobbying at the European level.

In 2018, she was awarded the European Press Prize (European Prize for investigative journalism)8,6 with Stéphane Foucart for their series on the "Monsanto Papers" published in Le Monde. In 2023, she was awarded by the European Conference on Tobacco and Health for her work on fake e-cigarette user organisations.