Purpose: The aim of this study was to investigate the current state of antidepressant prescriptions in breast cancer patients and factors affecting the prescription of antidepressants. Methods: This study targeted female breast cancer patients who were prescribed antidepressants by a psychiatrist at least once between August 2010 and July 2011 at the Asan Medical Center in Seoul. The prescription history of each study subject was investigated to analyze the current state of antidepressant prescriptions in breast cancer patients. Results: The analysis of the prescription histories of 136 subjects in the antidepressant group determined that escitalopram, mirtazapine, and trazodone were the three most commonly prescribed medications with an average of 1.54 antidepressants prescribed per patient. A logistic regression analysis showed a statistically significant increase in antidepressant prescriptions in patients who were divorced or widowed, had sleep disturbances, or had undergone oncologic surgery for the breast cancer (p<0.050). In contrast, the prescription rate was lower for patients with tumour sizes greater than 50 mm (p<0.050). Conclusion: The sociodemographic factor of marital status, clinical factors of sleep disorders and tumour size, and a treatment-specific factor of the use of surgical therapy were identified as affecting the prescription of antidepressants in female breast cancer patients.