Background: To evaluate the factors that have an impact on the development of brain metastasis in patients with breast cancer.Materials and Methods: Among the patients who were followed-up and treated for breast cancer between January 2000 and January 2010, the ones with brain metastasis were included to the analysis. Metastatic breast cancer patients without brain metastasis, which had similar duration of follow-up and median age were included as the control group. Both group were compared for prognostic and predictive factors in terms of relationship between with or without brain metastasis and survival.Results: There were a total of 63 female patients with metastatic breast cancer who had brain metastasis and the researchers enrolled the same number of female patients as the control... group. In the univariate analysis, as a significant finding, it was found that, the patients with breast cancer who had brain metastasis had vascular invasion positivity, human epidermal growth factor receptor-2 (HER-2) positivity, a rare detection of invasive lobular carcinoma component in the tumor, estrogen receptor negativity, and no bone and liver metastasis and they did not receive chemotherapy due to several reasons after the detection of metastasis in any organ. In the multivariate analysis, HER-2 positivity, no bone and liver metastasis and not receiving chemotherapy due to several reasons after the detection of metastasis in any organ were detected as significant findings.Conclusions: As the prognostic and predictive factors showing the development of brain metastasis in breast cancer patients may be identified, follow-up also including the brain is important in order to take preventive measures.