Objective To evaluate the necessity of anticoagulant therapy for totally implantable venous access port (TIVAP)-related asymptomatic deep venous thrombosis. Methods A retrospective analysis was performed for the patients with breast cancer receiving TIVAP who had detected nonocclusive, asymptomatic catheter related deep venous thrombosis (CR-DVT) and consultation in Department of Vascular Surgery, the First Affiliated Hospital of Chongqing Medical University from November 2014 to December 2016. The patients’ age, D-dimer level, the time that TIVAP was implanted in the body, treatment methods, ultrasonographic results, complications and followup results were analyzed. Results Only one TIVAP was removed before the end of all chemotherapy courses for catheter dysfunction. No concurrent infection or symptomatic pulmonary thromboembolism occurred. No bleeding event was reported during the anticoagulant therapy. Remission of CR-DVT seemed to have no correlation with age, the D-dimer levels at diagnosis and at the time of planned removal of infusion port, the time interval from TIVAP insertion to thrombosis onset, or the duration of TIVAP retention in the body (P > 0.05). Conclusions Anticoagulant therapy to these small, nonocclusive, asymptomatic TIVAP-related DVT does not show clear benefit. More researches are needed to figure out whether the asymptomatic CR-DVT is a physiological response for catheter implantation or a pathological state needing treatment.