Objective:To investigate the occurrence of catheter fracture in totally implantable venous access ports (TIVAP) and analyze its influencing factors.Methods:A retrospective nested case-control study was used to establish a cohort of 3 517 patients with TIVAP and infusion port maintenance in Affiliated Hospital of Qingdao University from January 2012 to December 2021, and they were divided into the fracture group and the control group. The general information questionnaire, TIVAP Catheter Fracture Related Factors Questionnaire and TIVAP Catheter Fracture Clinical Characteristics Questionnaire were used to collect general and clinical data of patients in two groups. The risk factors of TIVAP catheter fracture were analyzed by Logistic regression.Results:The incidence of TIVAP catheter fracture was 0.6% (21/3 517) . Logistic regression analysis showed that the operator's experience of placing ports, whether the patient performed TIVAP maintenance regularly, time for patients carrying the infusion port and whether TIVAP were repeatedly blocked were influencing factors for the occurrence of catheter fracture in TIVAP.Conclusions:Nursing staff should fully understand the risk factors of TIVAP catheter fracture, identify high-risk groups in the early stage and carry out targeted nursing interventions to reduce the incidence of TIVAP catheter fracture.