The studying on changes of serum concentrations of thyroid hormones FT3, FT 4 and TSH in 61 patients with primary nephrotic syndrome and 38 healthy individuals as control group. The results showed that 29.5 percent of patients with low serum FT3 level, 27.9 percent of patients with low serum FT4 level and 21.3 percent of patients with high serum TSH level compared to those of control group. The average serum FT3, FT 4 concentrations of patients were significantly lower than those of control group, p0.05 (FT3: 1.86 + or - 0.70 pg/ml versus 2.06 + or - 0.60 pg/ml
FT4: 0.75 + or - 0.24 ng/dl versus 1. 17 + or - 0.16ng/dl). The average serum TSH concentrations of patients was significantly higher than that of control group, p0.01, (3.96 + or - 2.45pUl/ml versus 1.58 + or - 1.17uUI/ml). FT31evel correlated positively to FT4, negatively to TSH level, r