This study aimed to investigate the gene polymorphism of the C242T p22phox in the population of Han nationality in Guangdong Province by randomly selecting 122 unrelated healthy candidates examined by means of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). It was found that the C and T allele frequencies were 0.934 and 0.066, and CC and CT+TT genotype frequencies were 0.877 and 0.123, respectively, in the population of Han nationality in Guangdong Province, suggesting the presence of C242T p22phox gene polymorphism with significant racial differences.