Objective: To study the single nucleotide polymorphisms (SNP) in the promoter region of tumor necrosis factor alpha (TNF-α)gene in Han population of Guizhou province. Methods: The five polymorphism sites at -1 031, -863, -857, -308, -238 in TNF-α gene promoter region were detected using PCR-RFLP and SSP-PCR and the data were analyzed statistically. Results: Allele frequencies of the five sites of TNF-α gene promoter region were obtained as the following: -238 G was 96%, -238 A 4%, -308 G 92%, -308 A 8%,-857 C 65%, -857 T 35%, -863 C 80%, -863A 20%, -1 031T 48%, and -1 031C 52% respectively. Conclusions: Unique characteristics exist in the SNP of TNF-α gene promoter region in Han population of Guizhou province. These results provide basic data for the study of the relationship between the polymorphism of TNF-α gene and the diseases.