Langerhans cell histiocytosis (LCH) is a malign proliferation of dendritic cells which are able to infiltrate any organ and system. LCH could be restricted to a single organ. In adults, LCH is usually restricted to the lungs. Skin involvement of LCH in adults is rare. However, in pediatric group, skin is a one of the predominant organ which LCH involves solely or as a part of systemic disease. Pediatric cutanoeus LCH demonstrates more clear clinical view compared to adult cutanoeus LCH. Skin lesions in pediatric cutaneous LCH usually affects the seborrheic regions of the skin, therefore to recognize and diagnose cutaneous LCH in children is unchallenging compared to adult LCH. In present article, a 33-year old patient with polydipsia and polyuria has been diagnosed as a central diabetus insipidus due to tumoral infiltration of cella turcica. The nature of the tumoral lesion has been revealed by histopathologic examination of single skin lesion which has been detected and sampled by dermatologist. In this case, diagnosis of adult type of LCH was challenging. However, detailed and total skin examination pawed the way toward the correct diagnoses and avoided from the transsphenoidal intervention. Since the skin biopsy is a low risk diagnsotic tool, detailed skin examination should be implemented and unusual skin lesion should be excised for histopathologic examination in a challenging adult LCH cases.