Three-month-old baby eating hands is great to consider is a normal phenomenon caused by the development of the organism, but also may be caused by diseases such as xenophagia. 1. Organism development: three-month-old babies eat hands a lot is usually due to the normal development of the baby caused by the physiological phenomenon, with the development of the brain, the baby will appear neural reflexes, there is something in the mouth, there will be the phenomenon of sucking, marking the baby’s ability to dominate the action has been improved. 2. Heterophagia: The pathogenesis and etiology of heterophagia are not clear, and it is considered to be caused by a variety of factors such as nutritional deficiency and mental psychology. The main symptoms of the affected children are often eat non-nutritious, non-edible food, etc., which will lead to the phenomenon of three-month-old babies appearing to eat a lot of hands. When three-month-old babies have the symptom of strong hand eating, it may be a normal physiological phenomenon caused by the development of the body, and does not need treatment. If it is caused by a disease, parents should take the child to the hospital in time and follow the doctor’s instructions for treatment.