【Objective】 To understand the polymorphism of D13S63 1 in Guangdong Han population. 【Method】 Short tandem repeat (STR) locus D13S63 1 was analyzed by means of polymerase chain reaction, following discontinuous el ectrophoresis system. 【Result】 Among 227 unrelated individuals from Guangdong Han population, 6 alleles rang from 197～217 bp could be observed. The most com mon allele with a frequency 0.2907 is allele 201 bp, the rare allele is allele 197 bp with a frequency 0.0903. The heterozygosity, the power of discrimination and the exclusion chance in paternity case were 0.7885，0.9231, 0.5543, respect ively. Segregation studies reveal that D13S631 inherit in Medel's Law. 【Conclus ion】 The result shows that locus D13S631 is highly informative and suitable fo r forensic application.