Baby teeth a little yellow is mainly caused by endogenous coloring or exogenous coloring. 1. Endogenous coloring: if infants take tetracycline drugs or drink water with excessive fluoride during the period of dental development, it will lead to abnormal development of dental tissues and symptoms of yellowing or defects; first of all, we must maintain oral hygiene and apply fluoride or filling treatment to the teeth when they are of age, and the yellowing of teeth is replaced by permanent teeth, which generally does not require special treatment. 2. Exogenous coloring: babies in breastfeeding or after eating, if not timely clean up the mouth, will form yellow tartar and other attached to the surface of the teeth; generally good oral care, after eating in time to clean up the teeth can be. Baby teeth a little yellow recommended timely medical diagnosis and symptomatic treatment, to avoid delaying the condition.