Background: Nephrotic syndrome is characterized by excessive urinary excretion of albumin and other intermediated-size plasma proteins such as transferrin.. Excessive urinary losses of transferrin can produce low serum transferrin level that may lead to low plasma iron concentration and consequently the development of iron resistant microcytic hypochromic anemia. The aim of the work to evaluate changes in serum iron and transferrin and the relationship between the serum and urinary transferrin in the active and remission state of nephrotic syndrome Patients and methods: The present work included fifty children with idiopathic nephrotic syndrome (INS), divided into 2 groups: group A (25 cases in activity) and group B (25 cases in remission). These two groups were age and sex matched with a mean age of (7.74 ± 2.45). All patients in this work were clinically evaluated together with routine laboratory investigations. Serum albumin and urinary alb. /creatinine were assessed. Levels of serum iron, serum ferritin, serum transferrin and urinary transferrin were measured.   Results: This work shows that the level of hemoglobin, MCV, HCT were statistically significantly lower in the cases in active state than cases in remission. The mean serum iron, serum ferritin and serum transferrin were significantly lower in the cases in active state than in the cases in remission .The mean urinary transferrin was statistically significantly higher in the cases in active state than in the cases with remission. Conclusion: Urinary transferrin can be considered a reliable parameter for early prediction of iron deficiency anemia in children with active nephrotic syndrome.