Infant developmental delay has more manifestations, mainly manifested as growth and development obviously lagging behind people of the same age, which is categorized into physical developmental delay, macromotor developmental delay, fine motor developmental delay, language developmental delay, and personal social and psychological developmental delay according to the difference of the ability area. The specific manifestations are as follows. 1. Physical developmental delay: mainly refers to the height or weight lagging behind peers by two standard deviations. The height and weight are significantly lower than those of babies of the same age. 2. Gross motor developmental delay: It is mainly manifested by the fact that the gross motor development is lagging behind that of babies of the same age. Specifically, you can refer to the DDST (Denver Developmental Screening Test), which is manifested by the fact that babies fail to pass the test on the 2 age lines. 3. Delayed fine motor development: similar to the delayed gross motor development, it mainly shows that the baby’s fine manual ability and drawing ability lags behind that of babies of the same age. 4. Delayed language development: babies often show that their ability to express themselves verbally lags behind that of babies of the same age. 5. Delayed development of personal social skills: it mainly shows the baby’s ability to respond to the people around him or her and his or her ability to live on his or her own. This part of the backwardness of the baby can be manifested in poor responsiveness and self-care ability. Parents are advised to bring their babies to the child health department of the hospital regularly for targeted intervention under the guidance of the doctor, which is conducive to the recovery of the babies.