8-year-old girl breast a little pain may be precocious maturity, trauma, breast disease and other causes. 1. Precocious puberty: 8-year-old girls usually eat too much estrogen-containing food or drugs, increase the body’s estrogen secretion, may trigger precocious puberty, stimulate mammary development, breast parenchymal hyperplasia or interstitial congestion, edema, breast pain. 2. Trauma: 8-year-old girl’s breast has been traumatic impact or injury, breast tissue damage may have breast pain. 3. Breast Disease: The chances of an 8-year-old girl having a breast disease are relatively small, but it can’t be completely ruled out, usually don’t pay attention to breast cleanliness and hygiene or excessive stimulation may lead to mastitis, and by the influence of inflammation, the breast has a red, swollen, and painful manifestations. The 8-year-old girl’s breasts hurt a little bit to go to the hospital to check whether it is physiological reasons or pathological reasons, and then targeted treatment.