Methylpredonisolone pulse therapy has been used widely on various diseases and pediatric kidney diseases. Renal blood flow analysis was done on 7 nephrotic patients and 3 lupus nephritis patients who were prescribed methylpredonisolone pulse therapy. On nephrotic patients, renal blood flow velocity was increased after methylpredonisolone pulse therapy. On the other hand, renal blood flow velocity was not changed remarkably on lupus nephritis patients. 14 year-old girl with lupus nephritis who had no response for methylpredonisolone pulse therapy, and renal blood flow velocity was decreased. This study shows that renal blood flow analysis is a useful examination for the efficacy of methylpredonisolone pulse therapy.