Although PEGylated filgrastim-induced aortitis is very rare and unknown clinically, some cases were reported and increasing, especially in breast cancer patients. The present study investigated the prevalence, clinical features and treatment of aortitis induced by PEGylated filgrastim in patients with breast cancer. A total of 2068 consecutive patients who underwent neoadjuvant/adjuvant chemotherapy with PEGylated filgrastim for breast cancer were enrolled. From the medical record, clinical, laboratory, medication, and imaging evaluation findings were collected. PEGylated filgrastim-induced aortitis was established in 0.3% of the study population. Common clinical presentations included extremely high fever and chest/back pain with high levels of inflammatory markers without any signs of infection. Contrast-enhanced computed tomography scans revealed typical enhancing wall thickening and periaortic soft tissue infiltration at various levels of aorta. All patients improved rapidly after treatment with modest doses of prednisolone (0.5 mg/kg/day) without any complications. Clinicians should be aware of aortitis as a possible complication of granulocyte-colony stimulating factor therapy, especially PEGylated filgrastim, given the frequent misdiagnoses in neutropenic patients undergoing chemotherapy.