It is true that patients with breast cancer undergoing endocrine therapy are prone to fatty liver after taking endocrine drugs, but it is also affected by factors such as the length of time of taking the drugs and the patient’s physical condition. The reason is that endocrine drugs can reduce the level of estrogen, which in turn reduces the decomposition of lipoproteins, and fat accumulates in liver cells and induces fatty liver. The treatment of breast cancer with endocrine drugs can inhibit and reduce the level of estrogen in the body, and then inhibit the growth of breast cancer cells, which has a therapeutic effect on breast cancer. Estrogen has the effect of inhibiting the breakdown of fat in the liver, and when the level of estrogen is lowered, the inhibitory effect on fat in the liver is reduced. The fat in the liver will gradually accumulate, which will lead to the formation of fatty liver, so it is easy to get fatty liver after taking endocrine drugs for breast cancer. It is recommended that in the process of taking endocrine drugs for breast cancer, patients should strengthen the detection of liver function, pay attention to reasonable diet to avoid the formation of fatty liver, and it is recommended to take them under the guidance of professional physicians.