There are many reasons for the left belly button soreness, such as urinary stones, intestinal obstruction, constipation and so on. 1. urinary stones: urinary stones can cause the left navel soreness, accompanied by lumbar soreness and discomfort phenomenon, through the routine urine examination can be found to contain red blood cells. 2. Intestinal obstruction: Intestinal obstruction will also show the left belly button soreness, accompanied by nausea, vomiting, belching (hiccups), stop defecation and other phenomena. 3. Constipation: Gastrointestinal dysfunction, improper diet can cause constipation, constipation can be severe left belly button soreness, usually after defecation will be relieved. The left side of the belly button is also seen in other causes, after the symptoms are recommended to go to the hospital in a timely manner to improve the examination, in accordance with the doctor’s instructions to take standardized treatment, do not ignore the symptoms, so as not to delay the condition.