The mammary glands are composed of skin fat, glands, blood vessels, nerves and ligaments, one on each side and basically symmetrical on both sides. The shape of the mammary glands is clinically categorized into 4 types, including hemispherical, conical, pendulous, and disc-shaped. Among them, hemispherical and spherical are considered to be the more aesthetically pleasing types. The size of the mammary gland is about 12-16cm in diameter and 5-6cm in height, the size of the nipple is about 0.2-0.4cm, the height of the nipple is about 0.5-0.6cm, and the size of the areola is about 3.5-4.5cm. The most important function of the mammary gland is lactation. However, it is currently believed that the mammary gland is not simply a breastfeeding organ, but also an aesthetic organ, in which the aesthetics of the mammary gland is determined by the size and sensation of the mammary gland, and the harmonization of the mammary gland size with the body is the best evaluation criterion for the appearance of the mammary gland.