To explore the effects of different sealing fluids of internal jugular venous tunnel-cuffed catheter on catheter-related blood stream infection (CRBSI) and catheter dysfunction in patients undergoing maintenance hemodialysis (MHD). Methods A total of 100 MHD patients who were treated in our hospital from January 2020 to July 2021 were selected, and divided into group A (35 cases), group B (31 cases) and group C (34 cases) by random number table method. For the three groups, heparin sodium saline, regular urokinase combined with heparin, and 4% sodium citrate were used for sealing, respectively. The incidence rates of CRBSI and embolism, and other relevant indicators were compared among the three groups. Results There was no significant difference in general data of the three groups (P＞0.05). The catheter embolism rate in group A was higher than that in group B or group C (P＜0.05). There was no significant difference in the incidence rates of tinnitus and hypotension among the three groups (P＞0.05). No significant changes of prothrombin time (PT), activated partial thromboplastin time (aPTT) and thrombin time (TT) were observed in the three groups before and after dialysis (P＞0.05). There was no significant difference among the three groups in above-mentioned coagulation function indicators at the same time point (P＞0.05). The urea clearance index (Kt/V) and effective blood flow of the catheter in group A were lower than those in group B or group C, and the usage time of catheter was longer than that in group B or group C (P＜0.05). However, there was no significant difference in these indexes between group B and group C (P＞0.05). There was no significant difference in CRBSI-free survival rate among the three groups at 2 and 4 months after treatment (P＞0.05), but the CRBSI-free survival rate in group A were lower than that in group B or group C at 6 months after treatment (P＜0.05). Conclusion Heparin sodium saline, regular urokinase combined with heparin, and 4% sodium citrate all can be used as sealing fluids of internal jugular venous tunnel-cuffed catheter in MHD patients. Regular urokinase combined with heparin and 4% sodium citrate can reduce the risk of CRBSI and catheter dysfunction, and prolong the service life of the catheter, compared with heparin sodium saline