Mastitis is divided into three periods, with different symptoms at different times. Mothers must be alert, and it is best to detect it during the bruising period, by pressing and rubbing it themselves or visiting the massage department of the hospital. The early symptoms of mastitis during breastfeeding are localized swelling, pain, less milk discharge, increased pain when the baby sucks, and painful localized breast lumps that can be touched and pressed. Some patients may have systemic symptoms, such as chills and high fever, headache, body aches and pains, thirst, dry stools, poor appetite, chest tightness and irritability. Pus-forming stage: until the breast is red, swollen, hot and painful for about 4-5 days, the affected breast lumps do not disappear or gradually increase in size, the local pain increases, or there is throbbing pain, or even persistent severe pain, accompanied by obvious tenderness, red skin color, burning skin, and strong fever does not subside, thirst for drinking, nausea and anorexia, swollen and painful lymph nodes in the ipsilateral axilla. The ulcerated stage: until about the 10th day of breast redness, swelling and heat pain, the central part of the breast lump gradually becomes softer and softer, pressed with a fluctuating sensation or see pus discharge from the nipple, local diffuse swelling and heat, pressure pain is obvious, and the general symptoms intensify. Special reminder to breastfeeding mothers: the early systemic symptoms of mastitis are very similar to the early symptoms of the flu, and many patients may mistake it for a cold and drink ginger soup and cover themselves with blankets, which will instead increase the area of milk stagnation or accelerate the evolution into a pus stage. Mothers should check their breasts carefully, and then combine the above symptoms to identify them without difficulty.