Idiopathic pulmonary hemosiderosis (IPH) is a rare complex entity characterized clinically by acute or recurrent episodes of hemoptysis secondary to diffuse alveolar hemorrhage. The radiographic features are variable, including diffuse alveolar-type infiltrates, and interstitial reticular and micronodular patterns. We describe a 3-week-old infant presenting with hemoptysis and moderate respiratory distress. Idiopathic pulmonary hemosiderosis was the first working diagnosis at the Emergency Department and was confirmed, 2 weeks later, by histological studies (bronchoalveolar lavage). The immunosuppressive therapy by 1 mg/kg/d prednisone was immediately started, the baby returned home on steroid therapy at a dose of 0,5 mg/kg/d. The diagnosis of idiopathic pulmonary hemosiderosis should be evocated at any age, even in the neonate, when the clinical presentation (hemoptysis and abnormal radiological chest images) is strongly suggestive.