We performed analysis of 79 childhood patients diagnosed as vitiligo and nevus depigmentosus in Tediatric Dermatologie Department of Seoul National University Hospital from March 1987 to September 1987. The results were as follows : 1. Of the 79 patients, 31 patients(39.2%) were vitiligo 21 patients(26.6% )were nevus depigmentosus and 27 patients(34.2%)were uncertain by cliniral diagnostic ctriteri.. 2. Viiligo began rarely in infancy(6.4% )and most appeared evenly in all childhood over 1 year old. Nevus clepigmentosus was present at birth in 57.1% of patients and was discovered within the first 6 months after birth in 42.9% of patients. 3. In vitiligo, most lesions were multiple. The most common site of involvement was the face, and there was this tendency of periorficial predisposition. In nevus ciepigmentosus, most lesions were solitary. The most, common aites of involvement were the lowed limbs and trunk, but there was no tendency of periorfcial presposition. 4. We found focal type of vitiligo in,51,6% of patients, vulgaris type in 32. 3 % acrofacial type in 9.6% and segmerital type in 6.5%. We also found isolated pattern of nevus clepigrnento us in 76.2% of patients, ciermatomal p<:ttern in 19.0ki and whorlec1 pattern in 4.8% The contrast enhiancement between the hypopigmented skin and nomal surrounding skin by Wood's light, examinatior reflected the epiclermal melanin pig merit, i. e., the more marked loss of pigmentation, the more accentuatian of the contrast The before, Wood's light examination without I:3OPA staining could help to ciiagnose the atisculte type of vitiligo showing eidermal melanocytes and nevu c.Iepigmeritosus.