Carcinomatous meningitis due to breast cancer is comparatively rare in Japan. Here, we report 4 cases of carcinomatous meningitis due to breast cancer. Meningeal metastasis was present in only 1 of the 4 cases, and the other 3 cases were associated with brain metastasis. Meningeal metastasis frequently causes symptoms associated with intracranial hypertension. Gadolinium-enhanced magnetic resonance imaging and cerebrospinal fluid cytology were useful for the diagnosis of meningeal metastasis. Multidisciplinary therapy, such as radiation and chemotherapy, was performed. Two of the 4 patients were treated with combined intrathecal administration of methotrexate and whole brain radiation. The quality of life was improved by multidisciplinary therapy.