6 months baby crying at night, may be physiological factors, may also be indigestion, iron deficiency anemia and other pathological factors. 1. Physiological factors: the baby’s nervous system is not yet mature, if too excited before going to sleep, will lead to the baby’s cerebral cortex cells in a relatively active state caused by the baby crying at night. 2. Pathological factors: (1) indigestion: the baby’s gastrointestinal function is developing, if parents feed improperly caused by gastrointestinal dysfunction leads to baby abdominal discomfort caused by the baby crying at night. (2) iron deficiency anemia: 6 months baby iron needs to increase, if the iron intake is insufficient will cause dizziness, sweating and other discomforts, resulting in the baby crying at night. 6 months baby crying at night, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause, under the guidance of the doctor to give targeted treatment or treatment.