Whether in neoadjuvant therapy or in adjuvant therapy, or in the treatment of advanced patients after recurrence and metastasis, targeted therapy has very good efficacy in patients with Her-2 positive breast cancer. Targeted therapy for breast cancer mainly targets Her-2 positive breast cancer. Currently, targeted therapy for Her-2 positive breast cancer mainly includes: trastuzumab, patuzumab, lapatinib and lenatinib. Targeted therapies have led to landmark advances in the systemic treatment of breast cancer. It is important to note that targeted drugs have more pronounced cardiotoxicity. Trastuzumab in combination with chemotherapeutic agents may increase myocardial damage, and in severe cases, heart failure may occur, so clinical monitoring of ECG is required. Breast cancer is a systemic disease, the current use of surgery-based integrated treatment options, patients should be based on their own situation, follow the doctor’s instructions to take a personalized treatment plan. Patients should take individualized treatment plan according to their own conditions and follow the doctor’s instructions. Please strictly follow the doctor’s instructions for medication, and do not use medication on your own.