Probiotics are a class of active microorganisms that are beneficial to the host. They are a general term for active beneficial microorganisms that are colonized in the human gut and reproductive system and can produce definite health effects to improve the host microecological balance and play a beneficial role. There are many benefits for children to take probiotics properly. (1) Probiotics colonize the human mucosa, forming a protective film that blocks the invasion of harmful bacteria. (2) Probiotics can also produce organic acids and natural antibiotics, and activate immune cells to inhibit the growth and reproduction of harmful germs. (3) Probiotics can produce B and K vitamins, which can promote the absorption of calcium, iron, phosphorus and zinc. (4) When taking antibiotics, timely supplementation of probiotics to the baby can effectively protect the baby’s gastrointestinal function. (5) Baby sickness, improper diet, soil and water discomfort, consumption of pesticide residues of fruits and vegetables, etc., will destroy the probiotics in the body, causing dysbiosis. The baby’s body leads to poor appetite, diarrhea or dry stools, bloating, poor absorption function causes malnutrition, etc. The appropriate amount of supplementation of beneficial bacteria to the baby can achieve a good preventive effect. Therefore, the appropriate amount of probiotics for babies can regulate the baby’s delicate intestines and promote the healthy growth of babies.