A case of lymphatic cyst of the adrenal gland in a 55-year-old woman is described. The patient presented with vague abdominal pain, and abdominal CT and ultrasonography suggested a pancreatic cyst. The cyst, 10x8x6 cm in size, was found in the left adrenal gland; it was multilocular and septated with thin walls that were lined by a single layer of attenuated cells. The lining cells gave a weak positive immunoreactivity against factor VIII-related antigen and Ulex eurapaeus, and ultrastructural study revealed the lining cells to be of endothelial origin. Together with small tiny proliferative cystic spaces were intermixture of the normal adrenal cortical cells in the transition zone between large cysts and adrenal cortex. No histologic distinction between cystic lymphangioma and lymphangiectatic cyst was obtained; instead, a term of lymphatic cyst seems preferred unless otherwise confirmed. With its classification, the pathogenesis of adrenal lymphatic cysts is reviewed.