Two-year-old baby poop once every three days can be seen in pathological conditions (such as functional constipation) and physiological phenomena, whether it is normal need to be judged according to the cause, such as the above phenomena and the previous bowel movement pattern is similar, and there is no obvious difficulties in defecation, is generally considered to be normal. 1. Pathological conditions: baby poop once every three days compared with the previous interval between defecation, the interval between defecation is significantly longer, or accompanied by dry stools, etc., affecting the defecation, the phenomenon of severe blood stools, considered as functional constipation, this situation is generally abnormal. 2. physiological phenomenon: such as the baby’s past bowel regularity, for 2 ~ 3 days to relieve a stool, and defecate smoothly, no abdominal discomfort, good growth and development, generally considered normal. It is recommended that two-year-old babies poop once every three days in time to consult a specialist physician to assess the judgment.