Background: X-chromosome (ChrX) STR loci have been proven to be a useful tool for paternity testing, especially in some cases. In paternity testing, genetic markers on ChrX are only applicable when the disputed child is female. Methods: The author investigated allele frequency distribution of ChrX STR loci DXS6789 and HumSTRX1 in a sample of unrelated individuals (males and females) in Han population living in Chengdu, China, by using PCR and PAGE followed by silver staining. Results: Ten and six different alleles of DXS6789 and HumSTRX1 loci were detected, respectively. The genotype frequencies of DXS6789 and HumSTRX1 loci were in good agreement with the Hardy-Weinberg equilibrium. The observed heterozygosity of DXS6789 and HumSTRX1 loci were 0.795 and 0.748 in females, respectively. Conclusions: It is suggested that these ChrX markers are appropriate for the purposes of forensic analyses.