Dual-targeted therapy for breast cancer has an effect on the liver. Dual-targeted therapy for breast cancer is similar to conventional chemotherapy, which is a more effective treatment for malignant tumors; for breast cancer, dual-targeted therapy is now the most effective treatment for breast cancer and a treatment with fewer side effects, as the drug has certain damage to human liver tissues, so attention should be paid to the individual patient’s liver function after taking the targeted drug. The liver of human body has the function of detoxification, if the liver function damage is serious and the condition of liver function is relatively poor, then when using double-targeted treatment, it will aggravate the liver function of human body and lead to irreversible complications; the treatment should be based on the patient’s own situation. The survival rate of early breast cancer patients who can be detected, diagnosed and treated early is very high. For the same disease, patients with different physical conditions have different treatment methods, and should undergo standardized treatment under the guidance of doctors.