Background: A public health student service was set up by the French government in 2018 with the aim of increasing awareness of primary health promotion among the 47,000 students of medicine and other health professions. It is an annual program involving community-based actions on nutrition, physical activity, addiction or sexuality. Our objective was to evaluate its implementation at local level and the different experiences of the stakeholders. Methods: A quasi-experimental study using process evaluation was performed in a Faculty of Medicine in Paris. Quantitative and qualitative data were collected from medical students who carried out preventive health actions, in the institutions in which the actions took place and from a subsample of beneficiaries. Results: One hundred and eight actions were carried out by 341 students in 23 educational or social institutions, mostly high schools (n = 12, 52%). Two thirds of the students did not feel sufficiently prepared to deliver preventive health interventions (65.7%, 224/341); however the beneficiaries found that the interventions were good (278/280, 99,2%). Nineteen (83%) of the host institutions agreed to welcome health service students again, of which 9 required some modifications. For students, the reporting of a satisfactory health service experience was associated with the reporting of skills or knowledge acquisition (p < 0.01). Delivering actions in high schools and to a medium-sized number of beneficiaries per week was associated with students' satisfaction. No effect of gender or theme of prevention was observed. For 248/341 (72.7%) students, the public health service program prompts them to address prevention issues in the future. Conclusion: The public health service undertaken by medical students through the program is a feasible and acceptable means of delivering preventive actions. Reinforcement of training and closer interaction with the host institutions would improve results.