Kaposiform infantile hemangioendothelioma (KHE) is a rare recently characterized, locally aggressive, endothelial-derived neoplasm that occurs exclusively in the pediatric age group. Milroy-Nonne disease (primary hereditary lymphedema) is an uncommon congenital entity with familiar history of lower limb edema as typical clinical features. An 8-year-old boy developed a hard painless mass in the right leg 7 years after the diagnosis of congenital primary lymphedema of the right lower extremity. Histopathological analysis of the tumor showed the typical findings of the KHE. To our knowledge this is the first reported case of a KHE engrafting on this infrequent benign lymphatic anomaly.