We report a sporadic case of ichthyosis bullosa of Siemens occurring in a Korean boy. In this report, the varied findings of the clinical features in one subject over five years are presented along with an investigation of the ultrastructural alteration. The patient had suffered from blistering, superficial peeling, and dark-grey colored lichenified patches on the extremities since infancy. As he grew older, the lesions were more localized to the elbows, knees, buttock and the dorsal aspects of the hands and feet, and were replaced by yellowish, lichenified plaques. Since the original report of Siemens in 1937, nine families including one sporadic case have been reported in the literature. To our knowledge, this is the second report of sporadic case of IBS.