Monilethrix is a rare familiar disorder of unknown cause, occurring in either sex, and ueually confined to the scalp. In most cases it is manifested in early childhood. lt is characterized by localized or widespread dystrophy of hair and follicles, the shafts showing regular variations in diameter producing alternate "nodes" and "internodes" which confer a striking beaded or moniliform appearance on the hair. We experienced a case of monilethrix, which was associated with keratosis pilaris and occurred in three generations. The patient's one sibling, mother, 4 uncles and 2 aunts of mother side and grandmother with her sister were all affected with a similar diaorder of hair.