Breast cysts are a very common condition in mammography. Common breast cysts include simple cysts and cumulus cysts. Simple cysts are the most common among breast cysts. It is mainly due to endocrine disorders causing ductal epithelial hyperplasia, dilation of breast ducts, and retention of secretions to form cysts. Cysts of accumulation of milk, also called milk retention-like cysts, are mainly due to obstruction of a duct during lactation, causing milk stasis and formation of cysts, which occur during lactation. Commonly, solitary cysts occur during non-lactation. For breast cysts, the diagnosis is mostly made with mammography ultrasound, which is less effective for mammography because of its lower density. In contrast, ultrasound is more sensitive for the diagnosis of cystic nodules and can accurately report the size, echogenicity, blood flow, and the presence of solid occupancy within the cyst. When the cyst is small, such as less than two centimeters, if the ultrasound does not find signs that can be, and the cyst condition is more stable, the method of regular observation can be adopted. Chinese medicine treatment can also be used, which is effective for the reduction of cysts and the regulation of endocrine disorders. For larger solitary cysts, if the cyst is already larger than three centimeters, ultrasound-guided puncture aspiration can be considered, which is more effective for some patients. After aspiration, pressure bandages are given to promote apposition of the cyst wall. However, the disadvantage of this method is that it does not destroy the cyst wall very well, so some patients have good short-term results, but the cyst wall may still continue to secrete over time and the cyst may still increase in size. Such cases can be treated by minimally invasive surgery, which means that the cystic fluid and the cystic wall can be aspirated through an orifice of a few millimeters in width with a minimally invasive rotary cutting device. This method not only aspirates the cystic fluid, but also causes sufficient damage to the cystic wall and is not suitable for recurrence. The traditional surgical method of complete excision of the cyst by incision has been used less frequently because of the high trauma and surgical scars. Some cysts have a tendency to be multiple, and if surgical treatment of breast disfigurement is serious, Chinese medicine can be used to regulate them to reduce new lesions and shrink existing ones. Although cysts themselves are benign lesions, the presence of cysts does not necessarily mean that they are benign lesions, as in the case of solid occupancies in the cysts we detected, which were later surgically confirmed to be intraductal papillomas. There are also some cysts with sudden bleeding that were later pathologically confirmed as ductal carcinoma in situ causing local bleeding. Therefore, attention should be paid to regular examination and careful differentiation.