Abstract Smoke-free campuses (SFC) prohibit smoking and vaping on all university grounds and for all users. Around a hundred of papers was published on that topic revealing how they reduce initiation and increase smoking cessation among students. Whereas it is key for the success of all project, including SFC, very rare research has investigated attitude of high-level leaders of universities toward SFC, their perceived barriers and motivation to adopt it. To fill this gap, we interviewed deans of medical schools in France, where SFC are limited. In-depth individual interviews were conducted on 31 deans and two associate-deans (representing 31 out of 35 French medical schools). Questions rose knowledge of SFC, perception of this measure, self-role to play and other factors influencing implementation. We targeted medical schools because they train future prescribers of smoking cessation, and can act as a model for policy dissemination to other schools. The 23 hours of interviews were analyzed using thematic analysis with Nvivo14. Regarding diffusion in 2023, only one medical school had a SFC, six were implementing it, 23 had no SFC and one abandoned it. 28 held positive attitudes towards SFC, explained by its impact on health and the mission of medical schools. Most of them considered SFC feasible with resources and engagement of students. Identified barriers were competing priority, lack of funding and of support from users and risk of stigmatization of smokers. A majority of deans thought they had a role to play in initiating, promoting and moderating the policy. SFC are recommended by the WHO but there is important room for improvement for their diffusion in France. Yet, a majority of deans we interviewed appeared motivated to adopt it. Solutions to encourage them and overcome barriers must be found. Key messages • Diffusion of SFC among medical schools remains limited in France. • Deans’s positive attitude towards SFC bring hope for a better diffusion of SFC among French universities.