Langerhans cell histiocytosis (LCH) is a rare proliferative disorder in which the pathologic Langerhans cells infiltrate and destroy the tissues. Patients with LCH present varied clinical manifestations. Cutaneous lesions in LCH manifest as vesiculopapular eruptions that often mimic various infectious diseases particularly in infants. We present a case of a female infant with an ulcerative lesion intraorally. The baby was asymptomatic otherwise. A detailed history revealed the presence of cutaneous lesions that was overlooked by her parents.CONCLUSION: This report tries to briefly discuss the current concepts regarding the etiology of LCH. An attempt has been made to emphasis the need for a through systemic examination. The protocol of investigative procedures to be adopted in LCH is also discussed.