Lipschütz ulcers are characterised by a first flare of non-sexually related acute genital ulcers (AGU) occurring in adolescent girls. Epstein-Barr primary infection is the most frequently reported aetiology but other infectious agents are probably implicated. We report the first case of mumps associated with an AGU in a 21-year-old girl. She presented a bilateral parotitis with genital ulcers, and serology confirmed she had mumps. As in our case, most Lipschütz ulcers heal spontaneously within a couple of weeks and the diagnosis should be reconsidered in case of recurrence.