One-year-old baby crying frequently at night may be caused by physiological factors, but may also be caused by pathological factors, such as rickets, gastrointestinal diseases and surgical diseases, etc., according to different causes to take targeted treatment. 1. Physiological factors: such as noisy environment, low temperature, excessive warmth, clothing discomfort, hunger and other factors can cause frequent crying, timely release of the cause of the baby’s symptoms will improve, such as creating a quiet sleep environment, maintaining the appropriate temperature and humidity indoors, and appropriate breastfeeding before bedtime. 2. Pathological factors: nutritional vitamin D deficiency rickets, the baby will have irritable crying, night terrors and other neurological symptoms of excitement, need to supplement vitamin D and calcium under the guidance of a doctor in a timely manner. (1) indigestion and other gastrointestinal diseases, the baby is mostly by bloating, diarrhea, loss of appetite and other symptoms, you can give bifidobacteria and other probiotics under the guidance of a physician to help digestion. (2) Surgical diseases: for example, congenital megacolon, the baby more difficult to defecate, abdominal distension and other symptoms, the baby is not easy to sleep, there will also be frequent crying, if necessary, need timely surgical treatment. If a one-year-old baby crying frequently at night may also have other reasons, it is recommended to consult a doctor in time, according to the cause of the disease, under the guidance of the doctor to give regular treatment. The use of medication should follow the doctor’s instructions.