Five months baby dry heaving, common causes include: physiological reasons, improper feeding, digestive system diseases. 1. Physiological reasons: five-month-old baby gastrointestinal tract development is still not perfect, there is a certain physiological gastroesophageal reflux, easy to cause the baby dry heaving, spitting up, overflow and so on. 2. Improper feeding: if the baby eat too fast, swallow a lot of air, overfeeding, etc. may cause the baby dry heaving, spitting up, parents need to feed a small number of times to avoid overfeeding, breastfeeding and timely burping to discharge excess air. 3. Digestive system diseases: acute gastroenteritis, indigestion, etc. may cause the baby dry heaving, vomiting, diarrhea, bloating and so on. Five-month-old baby dry heaving, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.