Abstract: This paper presents the preparation of Albumin (Alb) radioimmunoassay kit and its preliminary clinical application. The kit is mainly applied to the measurement of Alb concentration in human urine, adopting second antibody-PEG method. The measurement range is (1—50) μg/ml. The curve obtained with a serially diluted urine sample of high Alb concentration was a straight line. Recovery, detectability, intra and inter batch variation coefficients were 95.7％—103.6％, 0.1 μg/m1, 5.8％ and 6.4％ respectively. The kit was tried out clinically for measuring Alb in urine samples in about 1200 normal individuals and 600 various patients of related renal diseases, The preliminary clinical results show that Alb RIA is conducive to the early diagnosis of kidney function abnormalities.