Objective To investigate the relationship between putative rs5744168 of Toll-like receptors 5 (TLR5)and ANCA associated small vasculitis (AAV) in Guangxi Han nationality. Methods Polymorphism was analyzed by polymerase chain restricted fragments length polymorphism in 120 cases with AAV and 212 controls. Results (1)There were two genotypes of CC and CT in AAV group and control group. The frequencies distribution of CC and CT in 120 AAV patients were 82.50% and 17.50% respectively and the frequencies of allele C and T 91.25% and 8.75%,respectively. In controls,the genotypefrequencies of CC and CT were 88.68% and 11.3%, and frequencies of allele C and T 94.34% and 5.66%, respectively. No significant difference was found in either genotype distribution or allele frequencies between the patients and the controls ( P > 0 . 05 ) . ( 2 ) Significant reductions in the incidence of BUN, uric acid, quantitative test of 24 h urinary protein and erythrocyte sedimentation rate(ESR) were found in CC genotype (P < 0.05). (3) Binary regression model with a logit link function found total cholesterol was related with AAV. Conclusion The susceptibility of AAV in Guangxi Han population has nothing to do with the polymorphism of rs5744168.In AAV patients, polymorphism of rs5744168 may be associated with ESR, BUN, uric acid and quantitative test of 24 h urinary protein levels.