Abstract: Objective　To analyze the clinical characteristics, treatment, and prognosis of idiopathic pulmonary hemosiderosis (IPH). Methods　The study included 43 IPH cases who were hospitalized from January 2006 to January 2014 and followed up for more than 6 months. Their clinical data were retrospectively analyzed. According to the duration of oral prednisone treatment, the patients were divided into different groups and the relapse ratios were compared among groups. Based on the existence of relapse, the patients were divided into two groups to analyze the risk factors of relapse. Results　In 43 cases (24 males, 19 females) the median age of diagnosis was 4.1 years old (1.3-13.5 years). The main clinical manifestations were anemia, cough, hemoptysis, fever, and fatigue. Glucocorticoid can control the acute symptoms of IPH. Among the patients with oral prednisone treatment ≤ 1 year, -2 years, -3 years, and > 3 years group, there were no significant difference of relapse ratio (P>0.05). Long disease course (OR=1.13, 95%CI: 1.03-1.24) and hemoptysis at first visit (OR=9.91, 95%CI: 1.26-78.11) may be the independent risk factors of relapse. The vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1s (FEV 1) were negatively correlated with the course of IPH (r=-0.568, -0.597, -0.659 respectively, P<0.001). Conclusions　The manifestations of IPH are varied. Glucocorticoid is effective to control the acute symptoms of IPH. Prolonging the course of glucocorticoid therapy cannot reduce the relapse of IPH. Repeated relapse of IPH can cause restrictive ventilation dysfunction.