This study was designed to investigate the effects of Korean Lycii Fructus water extract in Pb-administered rats. The Pb exposed rats were given 100 ppm and 200 ppm in the distilled water. Sixty male Sprague-Dawley rats weighing between 90 and 110g were blocked into 6 groups according to body weight. The control group was fed a normal diet, without lead. The experimental groups, which was fed a normal diet plus 100 ppm and 200 ppm lead, and one group received a normal diet plus Lycii Fructus water extracts. The results: the Food intake, the weight gain, and the kidney weight content in the cadmium added groups were lower than those in the Lycii Fructus water extracts group. The contents of Pb in the kidneys of the rats were determined by using ICP(lnductively Coupled Plasma Spectrophotometer). The accumulation of lead in the kidney was lower in the Lycii Fructus water extracts group. The Plasma levels of renin activity was higher in the lead administration groups, as compared with the Lycii Fructus water extracts. Plasma levels of aldosterone activity was higher in the lead administration group, as compared with Lycii Fructus water extracts. These results suggest that Lycii Fructus water extracts has a lowering effects on the accumulation of pb on kidney and it is believed that the Lycii Fructus water extracts have some protective effects on lead-induced nephrotoxicity in rats, but the mechanism of these effects was obscure.