Summary.— The skin of 12 patients with the Chediak‐Higashi syndrome (C‐HS) have been studied by light and electron microscopy. In 6 homozygous patients there was almost complete absence of pigment in some but abundant clumps of enlarged melanin granules in both epidermis and dermis in others. In the dermis melanin was found within histiocytes, endothelial cells, perithelial cells, fibroblasts, Schwann cells, and free in the interstitium. Skin abnormalities were also observed in 6 heterozygotes. Those abnormalities were segmental basal deposition of normal appearing melanin pigment; clumping of slightly enlarged and irregular melanin granules; mild atrophy of the malpighian layer, with scattered cell vacuolization; and abundant melanin pigment within melanophores in the upper dermis where various degrees of mononuclear infiltration with intracytoplasmic inclusions were also observed.