X-linked adrenoleukodystrophy (ALD) is a rare genetic disorder caused by mutations in the ABCD1 gene, which causes the accumulation of very long-chain fatty acids (VLCFA) in both plasma and tissues, including the central nervous system. Since most ALD patients demonstrate neurologic symptoms and/or adrenal insufficiency-related phenotypes, clinical suspicion of ALD could be made based on these features. A 19-year-old male presented with hyperpigmentation of skin which began in the early teens. The pigmentation was prominent in the gums and palmar crease as well as in the elbows and the knees. The patient was referred to a pediatric clinic and underwent diagnostic workup for adrenal insufficiency and possible causes. Eventually, the patient was diagnosed with ALD accompanied by elevated VLCFA, adrenocorticotropic hormone, and a mutation in the ABCD1 sequence. There was no further abnormality found on physical examination as well as in the imaging studies including brain magnetic resonance imaging. Considering that neurologic involvement and adrenal insufficiency could be aggravated over time in ALD, early diagnosis and treatment are essential to prevent complications. Nevertheless, it is difficult to suspect ALD in patients without neurologic symptom as in our patient. Therefore, although it is very rare, the possibility of ALD should be considered as the underlying cause in patients with generalized hyperpigmentation of the skin