BACKGROUND/AIM: Risk factors for chemotherapy-induced nausea and vomiting (CINV) with anthracycline-containing regimen for breast cancer patients remain unknown. The risk factors for CINV with FEC100 were investigated. PATIENTS AND METHODS: Data on CINV events and patient backgrounds of 180 patients were collected from the first cycle of FEC100 treatment. In this regimen, patients were administered various antiemetics (ADs). The combinations of ADs were classified into four categories, while body mass index (BMI) was stratified into three categories. Risk factors were selected based on patient characteristics and combination of ADs. Risks for CINV were analyzed by univariate and multivariate analyses. RESULTS: In the univariate analysis of nausea, BMI was a significant factor, while BMI and combination of ADs were significant in vomiting. In the multivariate analysis concerning nausea, BMI was a significant factor. In the analysis concerning vomiting, the combination of ADs and BMI were significant. CONCLUSION: BMI was the most important risk factor for nausea and vomiting, while the combination of ADs was for vomiting.