Cystic lymphangiomas are rare, benign anomalies of the lymphatic system. More than 95% of cystic lymphangiomas occur in the head, neck, and axilla with only 1% in the retroperitoneum. Most of these cases are diagnosed by the second year of life with only a handful of adult cases. Once a symptomatic cystic lesion of the abdomen or retroperitoneum is diagnosed, treatment usually consists of surgical excision. Traditionally, surgery requires a laparotomy. This paper describes a patient with a retroperitoneal cyst who underwent a successful laparoscopic resection. The etiology and management of adult retroperitoneal cysts are reviewed as well.