Langerhans cell histiocytosis is a group of idiopathic disorders characterized by the abnormal proliferation of specialized bone marrow-derived Langerhans cells. In this report, we present a rare case of Langerhans cell histiocytosis with CT and MRI in a 2 yearold-boy who developed symptomatic diabetes insipidus and multiple bone ,cranial, lung and spleen metastases during the disease course. A 2-year-old male patient was hospitalized due to complaints of cough, fever, vomitting, diarrhea, achromasia, weakness and rash. Chest X-ray revealed reticulonodular infiltration in both lung fields. Thorax CT revealed diffuse micro and macro nodular type infiltration in both lung parenchyma. On CT and MRI revealed common lytic lesion of skull, vertebra and iliac bone. There are infundibular thickening and absence of posterior pituitary intensity on MRI of pituitary gland. The spleen involvoment is determined by abdominal CT. The diagnosis is confirmed with biopsy of iliac bone. Langerhans cell histiocytosis should be in the differential diagnosis in children having widespread lung, bone, pituitary gland, and spleen involvement on MRI and CT.