Abstract: An IgG RIA kit was established for determination of IgG in human serum and urine. The measurement range was 1—32μg/ml. Sensitivity was no more than 0.5μg/ml and recoveries were 94.7 to 107.0%. Intra- and inter-batch variation coefficients were 2.0—3.1% and 4.4—10.0% respectively.