Gynecomastia is a clinical condition caused by abnormal development of male breast tissue and abnormal hyperplasia of the connective tissue of the breast due to endocrine disorders caused by physiological or pathological factors. The main symptoms are breast enlargement, palpable lumps or painful swelling or tenderness, and occasionally local itching or nipple overflow, with an incidence of 30%-40% in young men. Gynecomastia is mainly related to sex hormones and can be classified as physiological, pathological and idiopathic according to the cause. Physiological gynecomastia occurs mostly in men during the neonatal period, adolescence and after middle age. The main manifestation of puberty is breast nodules or swelling, which often disappear naturally in 1-2 years. Estrogen stimulates the proliferation of breast tissue, while androgens antagonize the proliferative effect of estrogen. The temporary imbalance in the ratio of estrogen to male hormones causes gynecomastia during puberty. Pathological gynecomastia is often caused by medications, diseases, etc. The choice of treatment options is based on the cause. Physiologic gynecomastia with obvious clinical symptoms is treated with medication, such as oral methyltestosterone, and surgery if the effect is not obvious. For pathological gynecomastia, the first choice is to eliminate the cause, either by stopping the medication or by doing specific treatment for the primary disease, or by surgery if the result is not good. Although gynecomastia is a benign disease, it does not cause serious harm to the patient’s body. However, gynecomastia has a serious psychological impact on the patient and also affects the patient’s health. Traditional surgical methods for gynecomastia are gradually being replaced by plastic surgery, which is generally divided into three categories: (1) Sharp excision method. (2) Liposuction method. (3) Liposuction plus sharp excision method. Breast lumpectomy Subcutaneous breast gland excision Open excision, despite its large incision, is still performed under blind vision for the edges of the breast and is prone to incomplete hemostasis, uneven removal of tissue, and easy unevenness of the skin after surgery. The introduction of endoscopic surgical techniques into breast plastic surgery has reduced the incidence of bleeding, hematoma and postoperative nerve injury due to its small trauma, avoiding the large incisions and incisional scars of open surgery, and also avoiding damage to the vascular nerves. With the gradual improvement of surgical instruments such as wide view lumpectomy and ultrasonic knife, lumpectomy and lumpectomy-assisted surgery for breast diseases have been developed more rapidly and the technology is now more mature. After the operation, it quickly returns to the shape of a normal male breast with bilateral symmetry. The incision is chosen to be more hidden in the mid-axillary line because it is far from the anterior chest wall, avoiding the appearance of surgical scar, which becomes lighter with time and achieves a real cosmetic effect. As a minimally invasive surgical procedure, mammaplasty excision for gynecomastia is widely accepted by patients and can be a preferred surgical procedure for the treatment of gynecomastia.