Objective To study the relationships of lead concentrations and lead isotope ratios between adult blood and urine, and the area effects of lead isotope ratios. Method Lead concentrations and isotope ratios were determined by ICP-MS, and were corrected by CAIS for matrix effect. Results The lead concentrations in adult blood and urine may be significant differences in the same city, the lead isotope ratios in adult blood and urine also may be significant differences in the same city; the lead isotope ratios in adult blood in Beijing and Chengdu may be significant differences. Conehtsion The lead in urine could not reflect the lead concentration and lead isotope ratios in human body as a biomarker; the lead isotope ratio values in adult urine might depend on area difference; the human body may be able to fractionate the lead isotopes.