At present, breast hyperplasia is not a contraindication for the New Crown booster vaccine, so those who meet the vaccination requirements are able to make an appointment for the third New Crown virus vaccination. Mastoid hyperplasia is a long-term lobular proliferative lesion of the breast that is less affected by external factors, and current clinical evidence does not point to a correlation between the New Crown vaccine and mastoid hyperplasia. The contraindications for the first two injections of the New Crown inactivated vaccine and the third injection are more or less the same, which are for those who have allergic reactions, those who have had severe fever recently, and those who have recently taken relevant medications. Therefore, if a patient with breast enlargement has no adverse reaction to the first two injections, an appointment can be made for the third vaccination six months after the second.