There are many diseases that cause swelling and pain on the left side of the navel, and the following diseases are common: 1, intestinal obstruction, patients show swelling and pain on the left side of the navel, accompanied by nausea and even vomiting, anal exhaustion, reduced defecation, it is recommended that patients improve abdominal CT and other examinations. 2, constipation, mostly in elderly patients, due to poor gastrointestinal function leads to defecation difficulties, there will be swelling and pain on the left side of the navel, stools are often dry, patients can 3, urinary stones, in addition to abdominal distension, patients often feel pain and discomfort in the lower back, urinary routine can find red blood cells, need to do further ultrasound or CT clear diagnosis. So in summary, there are many diseases that cause distension and pain on the left side of the navel, and further diagnosis and treatment should be decided according to the specific clinical manifestations of the patient.