Chest pain in girls is common in three conditions: first, physiological chest pain, when women are in puberty or pregnancy, due to changes in hormone levels resulting in interstitial edema of the breast and chest pain, without special treatment, can be relieved. Secondly, cystic hyperplasia of the breast, which occurs in women aged 30-50, is caused by endocrine hormone disorders that lead to glandular hyperplasia and degenerative disorders. The clinical manifestation is pain in the chest with hyperplastic nodule-like changes, and the pain is related to the menstrual cycle. Third, acute mastitis, common in lactating women. It is an acute purulent infection of the breast tissue caused by bacterial infection of the breast tissue. At the beginning of the infection, the breast is only swollen and painful with an increase in skin temperature at the affected area, but when the infection is further aggravated, a breast abscess can be formed and a fluctuating lump can be palpated in the breast. Therefore, if a girl has chest pain, she should go to the breast surgery department for breast ultrasound to get a clear diagnosis and targeted treatment.