Excessive breast development results in breast enlargement, known as gigantomastia in women and gynecomastia in men. Moderate and full breasts are a beauty for women. Excessive breast enlargement, however, can also cause great mental and physical pain. Most people believe that a man’s chest should be firm and strong. If a man develops soft, high breasts similar to a woman’s, it can cause a strong inferiority complex, a condition known as gynecomastia. Gynecomastia can occur on one or both sides. Although genetics, medical disorders and some medications have been thought to be associated with gynecomastia, no exact cause can be found in most cases. The incidence has been on the rise in recent years. Gynecomastia (GYN) is a clinical condition in which abnormal development of male breast tissue and abnormal hyperplasia of the connective tissue of the breast are caused by an imbalance in the ratio of estrogen to androgen due to physiological or pathological factors.GYN is the most common male breast disease, accounting for about 80% to 90% of male breast diseases. GYN is physiological in 50% of cases and is most common in neonatal and adolescent years, when it is often transient and usually benign, but is considered abnormal if it occurs in prepubertal, young and middle age and requires further testing to rule out the possibility of breast cancer or other neoplastic organisms. If medication has not worked over time or if the breast has been enlarged for many years and has become a significant emotional burden for the patient, or if larger gynecomastia or cancer is suspected, surgical removal of the enlarged breast gland is required. Indications include: 1) males with breast development at the end of puberty or after puberty, with breast diameter >4 cm, where medication is ineffective; 2) males with severe aesthetic impact; 3) males with suspected malignant changes. Gynecomastia is curable, and there are many different methods. There are many ways to cure gynecomastia, including mastectomy and breast tissue aspiration. Mastectomy is the surgical removal of breast tissue and excess fat around the breast, and if the patient has extreme hypertrophy, excess skin is removed to reshape the breast. Swelling anesthesia mastectomy is the perfect surgical treatment for gynecomastia. It is performed by injecting a large amount of swelling anesthetic solution into the breast tissue and surrounding excess fat tissue, and then using specialized suction and scraping instruments to remove the breast tissue and excess fat.