It is normal for babies to roll over from 3 to 7 months of age, but there are individual differences. Rolling over belongs to the baby’s balance and gross motor development. Usually, babies can roll over from supine to lateral position at 3~4 months, and can intentionally turn upper and lower limbs around 7 months, and then the trunk, upper and lower limbs can be turned in segments, and can be rolled over from supine to prone position, and then rolled over from prone position to supine position. However, due to genetic and environmental factors, there may be individual differences. It is important to note that when babies are learning to roll over, parents should provide space and opportunities for babies to move in order to train their motor development. In addition, parents should watch over their babies when they roll over so that they do not fall out of bed or get bumped or bruised. If you suspect that your baby’s development is delayed, you should go to the hospital for a check-up to identify the cause of the problem and get timely treatment.