As an under-reported, severe, and life-threatening complication, catheter-related right atrial thrombosis (CRAT) can appear at any age with any type of central venous catheter (CVC). However, most reports are limited to hemodialysis patients with CVC. Totally implantable venous access port (TIVAP) is widely used for the infusion of high-concentration chemotherapeutic drugs in cancer patients. However, these catheters may cause CRAT.A 27-year-old female patient with TIVAP was referred for neoadjuvant chemotherapy because of breast cancer. At 60 days after TIVAP implantation, routine transthoracic ultrasound examination confirmed a mass of 3.4 × 2.5 cm in the right atrium (RA). The mass was attached to the atrial wall and close to the catheter tip. Initially, we chose systemic anticoagulation therapy, but it failed. Subsequently, we decided to adopt a combination of systemic thrombolysis and anticoagulation therapy via a cubital vein. After 9 days of treatment, the thrombus disappeared, and the TIVAP was eventually removed.Systemic thrombolysis and anticoagulation therapy seemed to be safe and effective for asymptomatic patients who had TIVAP-induced CRAT. We should position the catheter tip at the junction of the Superior Vena Cava with the Right Atrium during the implantation procedure in cancer patients undergoing chemotherapy.