The causes of redness in the balls of newborns include scrotal eczema and testicular torsion. 1. Scrotal eczema: Newborns with poor quality diapers, longer intervals between diaper changes, and guardians who don’t do a good job of hygiene in a timely manner can lead to newborns’ localized skin being in a contaminated and irritated environment, which can lead to scrotal eczema. 2. Testicular torsion: when the testicle is torsioned and the blood supply to the testicle is blocked, the testicle on the affected side will be red, swollen, painful and hardened, and the position will be elevated. There may be other reasons for the redness of the balls of newborns, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the doctor.