Purpose: Nanoxel®-M is a low-molecular-weight, non-toxic, biodegradable, docetaxel-loaded methoxy-poly (ethylene glycol)-block-poly (D,L-lactide) (mPEG-PDLLA) micellar formulation. We conducted a multicenter trial to evaluate the safety and toxicity of Nanoxel®-M and the quality of life (QoL) of Korean breast cancer patients treated with this formulation.Methods: Patients received adjuvant Nanoxel®-M with a schedule comprising four alternating cycles of doxorubicin with cyclophosphamide, followed by either Nanoxel®-M or Nanoxel®-M with cyclophosphamide after surgery for early breast cancer. We analyzed hematological and non-hematological toxicity profiles and alterations in patient QoL using the Korean version of the European organization for research and treatment of cancer core 30-item quality of life questionnaire. Fifty-five operable breast cancer patients with stage II or III disease were enrolled from four centers in Korea.Results: Regarding safety and toxicity profiles, grade 3/4 toxicity presented as anemia in 0.5%, neutropenia in 61.8%, febrile neutropenia in 4.5%, mucositis in 1.4%, and edema in 0.5% of patients during 220 total cycles. However, all-grade thrombocytopenia was not observed among hematological toxicities. No grade 3/4 nausea, vomiting, diarrhea, hand foot syndrome, dyspnea, allergic reaction, edema, or peripheral neuropathy were observed. Furthermore, no vehicle-related hypersensitivity reactions occurred when using Nanoxel®-M.Conclusion: Our findings indicate that Nanoxel®-M could be used to treat operable breast cancer patients, compare favorably with docetaxel in terms of hypersensitivity reactions and the incidence of taxane-induced peripheral neuropathy, and is associated with a similar incidence of febrile neutropenia.