To identify predictive factors for nephritis, relapse, and significant proteinuria in childhood Henoch-Schönlein purpura (HSP). Two hundred and six consecutive patients with HSP (93 female, 113 male), followed up at a single centre between 1996 and 2001, were analysed retrospectively. They were regularly monitored for clinical and laboratory parameters for renal sequelae and relapse. Nephritis was seen in 78 patients (38%), relapse in 52 (25%), and significant proteinuria in 39 (19%). In univariate analysis, an older age at onset (>10 years), persistent purpura, severe bowel angina, and relapse were identified as factors associated with nephritis and significant proteinuria. Relapse-related factors were an older age, persistent purpura, severe bowel angina, and leucocytosis. Logistic regression analysis showed that nephritis was significantly associated with an older age, persistent purpura, and relapse, and significant proteinuria was closely related to severe bowel angina and relapse. We identified some predictors for nephritis, relapse, and significant proteinuria in childhood HSP, and close attention should be paid to those patients with the risk factors, such as an older age at onset, persistent purpura, severe bowel angina, and relapse.