Abstract: OBJECTIVE o investigate the association of catheter-related bloodstream infection (CRBSI) with vitamin D receptor (VDR) gene polymorphism in long-term hemodialysis patients. METHODS Totally 130 patients with long-term hemodialysis in hemodialysis center of Yantai Yuhuangding Hospital between Jan. 2020 and Dec. 2020 were selected as the study subjects, and were divided into infection group (n=34) and control group (n=96) according to whether CRBSI occurred. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RELP) was used to detect the polymorphism of VDR gene at Apa I (rs7975232) locus, and the levels of serum vitamin D25(OH)D₃, procalcitonin (PCT), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected, and the influencing factors of CRBSI occurrence were analyzed. RESULTS There were no statistical differences between the actual frequencies and the theoretical frequencies of genotypes at Apa I locus of VDR gene in the two groups, which were representative of the group. The frequency of CC genotype at Apa I locus of VDR gene in infection group was lower than that in control group (P<0.05), while the frequencies of AA genotype and A allele were higher than those in control group (P<0.05). The level of serum 25(OH)D₃ in infection group was lower than that in control group (P<0.05), while the levels of PCT, IL-6 and TNF-α were higher than those in control group (P<0.05). In the infection group, the level of serum 25(OH)D₃ of patients carrying AC genotype or AA genotype was lower than that of patients carrying CC genotype (P<0.05), while the levels of serum PCT, IL-6 and TNF-α were higher than those of patients carrying CC genotype (P<0.05). Multivariate Logistic regression analysis showed that AA genotype and A allele at Apa I locus of VDR gene were the influencing factors for CRBSI in patients with long-term hemodialysis (P<0.05), and serum 25(OH)D₃ was its protective factor (P<0.05). CONCLUSION The development of CRBSI in patients with long-term hemodialysis was associated with VDR gene polymorphism, and was also affected by 25 hydroxyvitamin D₃ levels and related inflammatory factors.