Abstract: 　Objective　To analyze the long-term prognosis and prognostic factors of idiopathic collapsing focal segmental glomerulosclerosis (FSGS) and not otherwise specified FSGS in children. Methods　The clinical, pathology and follow-up data of patients with idiopathic collapsing FSGS and not otherwise specified FSGS were analyzed retrospectively by Kaplan-Meier method, univariate and multivariate Cox regression analysis. Results　A total of 64 patients (29 idiopathic collapsing FSGS and 35 not otherwise specified FSGS) were diagnosed by renal biopsy. The 4-year renal survival rate of idiopathic collapsing FSGS and not otherwise specified FSGS were 48.3%, 74.3% respectively. Univariate analysis revealed that the renal survival time were 25.41±3.28 months in idiopathic collapsing patients, and 35.53±2.73 months in not otherwise specified patients. The different is significant (χ2=4.07， P=0.044). Multivariate Cox regression analysis showed that poor treatment response (HR=5.92, P<0.05) and renal insufficiency at early stage (HR=2.45, P<0.05) were independent risk factors of prognosis. Conclusions　Compared with patients with not otherwise specified FSGS, the renal survival time is shorter in idiopathic collapsing FSGS patients. Patients with renal insufficiency and poor response to treatment have poorer prognosis.