A three-year-old child’s constant blinking and rubbing of the eyes may be caused by habitual blinking, eye diseases, and Tourette’s syndrome in children. 1. Habitual blinking. Three-year-old children’s curiosity, imitation ability is strong, may other people’s habits, thus causing the phenomenon of always blinking and rubbing eyes, which is a normal factor. 2. Eye diseases. Due to insufficient tear secretion and other reasons, causing dry eye, eye dryness, which leads to children often blinking and rubbing their eyes. Suffering from inverted eyelashes, entropion and other diseases, it is easy to rub the eyeball and cornea, thus forming the above symptoms. Suffering from infectious inflammatory diseases such as conjunctivitis and keratitis, symptoms such as frequent blinking and tearing occur, which leads to frequent eye rubbing. 3. Tourette’s syndrome in children. Tourette’s syndrome in children is caused by hereditary reasons, which leads to symptoms such as blinking and rubbing the eyes and unconsciously clearing the throat. Three-year-old children are always blinking and rubbing their eyes may also be related to other causes, and should go to the hospital in time, in order to clarify the cause of the disease, standardized treatment.