Retroperitoneal cystic lymphangiomas are uncommon tumors usually found incidentally at surgery, autopsy, or lymphography. When clinically significant, they usually present early in life as a palpable abdominal mass . We discribe an unusual case of a six-year old boy who was operated for a cystic lymphangioma of the right axilla at the age of five months, and , six years later, was found to have a retroperitoneal cystic lymphangioma accompanied with motor weakness of the lower extremities.