Multicystic peritoneal mesothelioma (MPM) is a rare and benign condition. Its treatment is surgical. After surgical resection, MPM tends to recur in the peritoneal cavity. Our observation concerns a 30-year-old patient with a history of non-specific abdominal pain evolving for a year. She was operated on urgently and benefited from a resection of cystic lesions disseminated in the peritoneal cavity in addition to an appendectomy. The peritoneal cancer index (PCI) was estimated at 12 points. The postoperative course was simple. The histological study was in favor of a multicystic peritoneal mesothelioma. Despite the fact that the patient was asymptomatic and a normal CT scan 3 months postoperatively, a second look was retained and the patient was operated on again. Residual cystic lesions of 04 to 15mm were highlighted and resected. This surgery was associated with intraperitoneal chemotherapy based on 150mg of Cisplatin over 5 days. The postoperative course was simple and the patient was discharged from the service on the 10th postoperative day. A third intervention by laparoscopic approach was carried out five years later for the exploration of primary sterility. The latter found a cyst of the left ovary and a hydrosalpinx which were resected. She is alive and without recurrence at 108 months. Conclusion:Faced with MPM for which there is doubt about radical resection, additional surgery using a second look should be considered. This attitude makes it possible to avoid residual recurrence, which is quite frequent in this disease.