Langerhans cell histiocytosis is a rare disease in childhood. It has a very polymorphous clinical expression, ranging from a single bony disease to a multisystemic disease involving vital organs. Prognosis has been improved by use of chemotherapy. We report a 2-year-old girl with multifocal Langerhans cell histiocytosis of bone and skin, revealed by a pain of the left hip and a limp trailing from 2 months. The diagnosis has been established by histological exam. The patient received chemotherapy and steroids. Outcome was favourable over 6-month follow-up. Trailing limp should evoke diagnosis of Langerhans cell histiocytosis. Skin biopsy should be preferred to a bone biopsy because of its safety.