Schwannoma is a rare benign tumor that comes from the SCHWANN cells that sheath the peripheral nerves. Retroperitoneal location is even rarer than the frequency of this neoplasia. The diagnosis is immuno-histochemical and the treatment is surgical. We report the case of a 36-year-old patient with abdominal pain and transit disorders for 4 months. An abdominal CT scan was found a rounded tissue mass of 10 cm long with well-defined borders. The patient was prepared for surgical removal. Per-operatively, a mass was found in the sub hepatic area, pushing the right kidney backwards. Anatomo-pathological examination was in favor of Schwannoma.