Early breast-conserving radiotherapy for breast cancer will not feel pain, and the corresponding pain will appear only in the middle and late stages of radiotherapy. Breast-conserving radiotherapy is in fact a method of using rays to irradiate the tumor area, preventing and treating the tumor through rays, and there is no obvious pain. However, in the middle and late stages of radiotherapy, due to the increased number of chemotherapy treatments, it is very likely to lead to the emergence of complications, mainly radiological neuritis, radiological dermatitis and other diseases, which will cause some pain comparatively speaking. Breast cancer patients don’t need to worry too much about the pain caused by breast-conserving radiotherapy, the early stage is not painful, and the pain in the middle and late stages is relatively mild, which is acceptable to most of the patients, and the patients should cooperate with the doctors to carry out active treatment.