Dermoid cyst is the most frequent benign ovarian tumor. Its spontaneous or more frequently iatrogenic intraperitoneal rupture may lead to a chemical peritonitis. This is a rare complication but with a potentially dangerous issue. We report a case of a patient who developed chemical peritonitis after laparoscopic management of ovarian dermoid cysts. Three further interventions, associated with systemic anti-inflammatory treatment, were necessary to resolve symptoms completely. On the basis of this case, we aim to re-access the characteristics of dermoid cysts and highlight in particular the potential complication of chemical peritonitis and the following attitude to avoid this.