We report the case of a 16-year-old girl explored for an ascite of great abundance responsible for a respiratory embarrassment. Its symptomatology proved to be secondary to a vitelline tumour of the ovary. It required several drainings of ascite before surgical operation. She had a conservative treatment followed up by a chemotherapy which allowed a clinical and biological remission. We report this observation considering the originality of the mode of revelation of the tumour. We insist in addition on the possibility of a conservative treatment.