We have experienced a case of infantile nephritic syndrome confirmed by renal biopsy in a 13-month-old female patient who showed and develop mental retardation and persistent proteinuria. She revealed mild eyelid edema, joint laxity, delayed speech development and adrenal cortical calcification on the radiologic study. Renal biopsy showed microcystic tubular change, micro-glomeruli and marked mesangial proliferation.