Introduction: In France, the spread of a hypervirulent strain causing invasive meningococcal disease of serogroup W (MenW) has been observed since 2015/16. We describe a cluster of three MenW cases, resulting in two deaths, that occurred in late 2016 on a university campus, and the vaccination campaign that was subsequently organized. Methods: Epidemiological and microbiological analyses led a multidisciplinary expert group to recommend the organization of a mass vaccination campaign using the ACWY vaccine targeting more than 30,000 students and staff on the university campus. Individual vaccination data were collected using the lists of students and staff registered at the university to estimate vaccination coverage. Results: Three MenW cases occurred within a 2-month period among students in different academic programs. All three isolates were identical and belonged to the "UK-2013 strain" phylogenetic branch. The attack rate was 10.8 per 100,000 students. The vaccination campaign was organized only 15 days after the third case occurred. In total, 13,198 people were vaccinated. Vaccine coverage was estimated at 41% for students at the university and 35% for university staff. Conclusion: Timely notification of cases to health authorities was essential for detecting the cluster and rapidly implementing the vaccination campaign. No further cases occurred on campus in the year following the vaccination campaign. This episode represents the second cluster of MenW caused by the "UK-2013 strain" at a university since 2016.