Angioma serpiginosum is a rare acquired naevoid disorder, characterized by minute red or purple punta that are frequently arranged in serpiginous patterns in the lower extremities and buttocks. It usually begins in childhood and is more common in females. Histopathologically, thin-walled capillaries in the dermal papillae and the superficial reticular dermis are widely dilated without extravasation of red blood cells. We report a case of angioma serpiginosum on the lateral aspect of the right arm along the lines of Blaschko in a 36-year-old woman. (Korean J Dermatol 1998;36(3): 520-523)