This article focuses on the stories of key women scientists (Rachel Carson, Anita Conti, Aliette Geistdoerfer, Elinor Ostrom and Elisabeth Mann Borgese) who had a major impact on ocean conservation. Through these portraits of women scientists from the Western world, we study their trajectories in the professional world of the sea, an environment largely dominated by men, and we explore the intangible heritage of these courageous pioneers, in order to understand their impact on today's generations of ocean scientists. Their works have allowed to develop a better understanding of marine ecosystems and of the coastal communities that live off the sea, and to raise awareness on the impacts of overexploitation and the need to better preserve the ocean. They all contributed to making the protection of the marine environment an international political issue. The authors aim to contribute to a necessary historical and sociological reframing of the epistemology of ocean sciences. The aim of this article is not to provide a sociological gender analysis, but rather to give an overview of women leaders in ocean science who have paved the way for new ways of thinking about the ocean and its governance.