Oral admission of pyrotinib together with radiotherapy can significantly increase the overall response rate, progression‐free survival, time to progression and duration of response of HER2+ brain metastatic breast cancer patients, without causing extra adverse events. Pyrotinib might be an effective medication to enhance the tumor radiosensitivity of HER2‐positive brain metastatic breast cancer patients. Here, ERBB2 is linked to neoplasm.