Objective　To explore the causes of acute renal failure resulted from tacrolimus in the treatment of nephrotic syndrome. Method　The clinical data of acute renal failure caused by tacrolimus in treatment of nephrotic syndrome in 3 children during January 2012 and December 2015 were retrospectively analyzed. Results　There were 2 male and 1 female aged 3, 11， and 13 years respectively. Clinical manifestations were consistent with simple type of primary nephrotic syndrome. One child was frequently recurrent and another two were secondary steroid resistant. The renal pathology showed minimal changes. Acute renal failure occurred within 4 weeks after treatment with tacrolimus on the basis of hormone therapy in all patients who had infection within one week. Renal function recovered to normal within 2 weeks after discontinuation or reduction of tacrolimus combined with anti-infection and diuresis treatment. Two children continued with tacrolimus, but the other one was replaced with cyclosporin A. The renal function of all patients remained normal during the follow-up for 10-42 months. Conclusion　In the first 4 weeks of tacrolimus therapy in children with nephrotic syndrome, infection may lead to reversible acute renal failure.