Infants do not poop only fart, may be a physiological manifestation; but may also be the occurrence of congenital megacolon, or gastrointestinal dysfunction. 1. Physiological factors: may be in the process of sucking milk swallowed a lot of air, when the gas accumulation in the body caused by flatulence, food accumulation and other conditions, there will be obvious intention to poop, farting without pooping performance. 2. Congenital megacolon: it belongs to a kind of intestinal ganglion deficiency disease, which is easy to cause stubborn constipation, abdominal distension, and can cause low intestinal obstruction. If the stool is not easy to be discharged during defecation, there will be the phenomenon of only defecating but not pooping. 3. Gastrointestinal dysfunction: when the gastrointestinal dysfunction, easy to cause constipation, gastrointestinal flatulence, food accumulation, etc., defecation may be the discharge of gas without stool. Babies do not poop only fart, there may be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.