Abstract: With a nationwide increase in elderly population, an increased number of breast cancer diagnosed in older women is expected. Nowadays, targeted therapy is an important systemic treatment for human epidermal growth factor 2 (HER-2) positive breast cancer, which has been playing an important role in the treatment for breast cancer. It is controversial whether trastuzumab should be used for targeted therapy in elderly Her-2 positive breast cancer patients with moderate risk and no cardiac disease. Current evidence suggests that patients aged 60-70 years old with a moderate risk of Her-2 positive breast cancer may benefit from trastuzumab with an acceptable and reversible risk of heart events. Yet there is no enough evidence for elderly patients beyond 70 years old. Therefore, we should balance the benefit and risk when considering targeted therapy for elderly patients with breast cancer. Management of breast cancer in the elderly should take the will of the patients, the physical condition, and comorbidities in to consideration. Anthracycline-based chemotherapy should not be used together with targeted therapy. It is necessary to monitor cardiac function and deal with heart events timely.