Objective · To investigate the incidence, risk factors and treatment of the catheter-related thrombosis (CRT) in breast cancer patients after implantation of totally implantable venous access port (TIVAP) in chemotherapy. Methods · A total of 190 cases after implantation of TIVAP were investigated. Color Doppler ultrasound was used to monitor the neck blood vessels to find whether there was CRT before chemotherapy and before taking out the port. The incidence of CRT, occurrence time, risk factors and treatment efficacy were observed. Results · There were 112 (58.9%) cases with CRT and 108 (56.8%) patients with asymptomatic thrombosis, and only 4 cases had symptomatic thrombosis, the incidence of which was 2.1%. Most thrombosis developed on the 21th day after catheterization, and the patients over the age of 60, with clinical stage III – IV and chemotherapy regimens TEC (docetaxel combined pirubicin and cyclophosphamide) were the risk factors for thrombosis. All the patients with asymptomatic thrombosis accepted anticoagulant treatment with low molecular heparin, earthworms enzyme or aspirin, respectively, but there was no significant difference in efficacy in the three groups (P=0.743). Conclusion · Port catheter related symptomatic thrombosis incidence is low but the incidence of symptomatic thrombosis is high in the breast cancer patients after chemotherapy. Age, tumor stage and TEC chemotherapy regimens are the risk factors for catheter-related thrombosis.