The following reasons are common for children to cry at night: 1) the environment temperature is too high or too low, wearing too thick or too little. 2) insufficient breastfeeding at night, caused by hunger.3) Difficulty in raising temperament, temperament is inherent, divided into difficult to raise, easy to raise and intermediate, difficult to raise temperament babies in the process of bringing up the baby is more difficult to go to the Children’s Health Division for temperament assessment, to give the necessary early training.4) Early manifestation of brain injury, while Accompanied by head easy back, hands clenched fist, breastfeeding difficulties and other manifestations, combined with the existence of high risk factors before, during or after birth, should be timely to the Children’s Rehabilitation Department for consultation. 5, vitamin D deficiency rickets, can be given to supplement the vitamin D gelatin pills and calcium, supplementation for a period of time will gradually get better.