Objective To investigate the relationship of TNF-αgene promoter 308 locus(TNF-α-308)polymorphism with the susceptibility and severity of central venous catheter-related sepsis(CRS). Methods One hundred and five CRS patients admitted in Kaihua People's Hospital from January 2015 to May 2017 were enrolled in the study.According to whether complicated with multiple organ dysfunction syndrome(MODS), they were divided into CRS complicated MODS group(n=34)and CRS non-MODS group(n=71).Meanwhile,210 patients with no catheter-related infection(case control group)and 105 healthy subjects(healthy control group)were also enrolled in the study.Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP)was used to genotype TNF-α-308, and the relationship of TNF-α-308 polymorphism with the susceptibility and severity of CRS was investigated.SPSS 16.0 was used to analyze the data.Results There were no significant differences in frequencies of GG, GA,AA genotypes and G,A allele of TNF-α-308 among CRS group,case control group and healthy control group(χ2=2.262 and 0.907,both P>0.05).Compared with CRS non-MODS group,case control group and healthy control group, the frequency of GG genotype was significantly lower and the frequencies of genotype GA and AA of TNF-α-308 were significantly higher in CRS MODS group(χ2=8.809,7.700 and 9.220,all P<0.05).Compared with CRS non-MODS group,case control group and healthy control group, the allele frequencies of G were significantly lower and allele frequency of A allele of TNF-α-308 was significantly higher in CRS MODS group(χ2=9.823, 8.624 and 7.654, all P<0.05).There were no significant differences in genotype frequency and allele frequencies of TNF-α-308(χ2=0.852 and 0.975, both P>0.05)among CRS non-MODS group and case control group,healthy control group(χ2=1.022 and 0.535,both P>0.05).The odds ratio of GA +AA genotype and A allele of TNF-α-308 in CRS MODS group were 2.664(95%CI 1.259-5.639)and 2.440(95%CI 1.326-4.490).Conclusion TNF-αgene promoter 308 locus polymorphism is not a predisposing factor for CRS, but may be associated with complication of MODS in CRS patients.