Schwannoma is the most common type of peripheral nerve tumor, which arise from Schwann cell of nerve sheath, and most are amenable to surgical cure with minimal morbidity. The majority of schwannoma is found as incidental, slow-growing masses attached to large nerve trunk. We experienced a rare case of retroperitoneal schwannoma presented as malignant adnexal mass in fifty three-year-old perimenopausal woman. Here we present the case with brief review of literatures.