Abstract: OBJECTIVE To explore the tumor necrosis factor-α（TNF-α） gene polymorphism of the abdominal surgery patients with postoperative abdominal fungal infection. METHODS A total of 62 patients who underwent surgery in general surgery department of the Affiliated Hospital of Dazhou Polytechnic from Jun 2017 to Jun 2020 and had postoperative abdominal infection were recruited as the study group, meanwhile, 80 patients who underwent surgery in general surgery department but did not have postoperative abdominal infection were chosen as the control group. The rs1800629 and rs1799964 loci of TNF-α gene were studied, the genotypes were detected by using polymerase chain reaction-restriction fragment length polymorphism（PCR-RFLP）, and the genotypes were compared between the two groups. RESULTS The frequencies of rs1800629 G/A locus AA genotype and allele A of the study group were respectively 35.48% and 50.00%, significantly higher than those of the control group, the frequency of allele G of the study group was 50.00%,significantly lower than that of the control group（P＜0.05）. There were no significant differences in frequencies of rs1800629 G/A locus GG genotype, AG genotype of TNF-αgene, rs1799964 G/A locus GG genotype, AG genotype, AA genotype of TNF-α gene and G/A allele between the two groups. The risk of abdominal fungal infection was significantly increased when the TNF-α gene rs1800629 G/A locus under the recessive model, homozygous model and plus risk model（OR=1.335,2.341,2.185）. The gastrointestinal dysfunction score, negative pressure and death toll of the patients carrying with AA genotype at rs1800629 G/A locus of TNF-α gene were significantly higher than those of the patients carrying with AG/GG genotype（P＜0.05）. There were no significant differences in the length of intensive care unit（ICU） stay and mechanical ventilation duration between the two groups. CONCLUSION The increase of frequencies of AA genotype at rs1800629 locus of TNF-α gene and allele A may remarkably increase the susceptibility to the abdominal fungal infection, which is not associated with the rs1799964 locus.