Complementary foods for infants are usually added at 6 months of age. Babies before 4 months, because the digestive system is not yet mature, the activity of various digestive enzymes is relatively insufficient, so within 4 months it is recommended to exclusively breastfeeding, if breastmilk is insufficient or for other reasons can not be breastfeeding, you can formula feeding. 6 months is the appropriate age to start adding complementary foods, because at this time the baby is interested in other people to eat, and can over take their own food; at this time like to put something into the mouth, and can control the tongue well, so that the food in the mouth to move, can be through the upper and lower jaw opening and closing movement for chewing. Complementary foods added in the initial stages should be foods that are easy to swallow and digest and do not cause allergies. Iron-fortified cereals, such as iron-fortified rice powder, etc.; vegetables such as white radish, carrot, pumpkin, tomato, spinach puree, etc. are common choices; and fruits such as apples, bananas, pears, papaya puree, etc. are common. When adding complementary foods, we should strictly follow the principle of adding complementary foods, that is, from less to more, from thin to thick, from fine to coarse, etc., and at the same time, we should pay attention to observe whether the child has a rash, diarrhea, and other symptoms of food allergies, once abnormal, we should stop adding and take the child to the hospital in a timely manner to the Department of Pediatrics for medical attention.