Four Chinese populations have been studied by the polymerase chain reaction (PCR) for obtaining the data on genetic polymorphisms of D19S400 locus in four populations in China and for evaluating its use in forensic practice. EDTA-blood samples were collected from 356 unrelated individuals in Nanning (Zhuang), Dali (Bai), Lasa (Tibetan); Hailaer (Mongolian), DNA samples were extracted by Phenol/Chloroform method. The PCR products were analyzed by PAG vertical electrophoresis. Nine alleles and 42 genotypes were found at D19S400 locus in these four populations. The heterozygosity was between 0.75 and 0.89 and the discriminating power between 0.9274 and 0.9625. Significant difference was observed in the distribution of allele frequencies among the four Chinese populations. According to the results obtained in this study, D19S400 locus is a useful marker for individual indentification, paternity testing and for genetics study.