Vague pain in the left lower abdomen after eating is commonly caused by the following: 1, intestinal diseases, such as chronic colitis, intestinal tumors, intestinal obstruction, etc., can cause symptoms of vague pain in the left lower abdomen after eating. Patients are often accompanied by nausea, vomiting, diarrhea, blood in stool, etc. It is recommended to do abdominal X-ray examination, colonoscopy to clarify the diagnosis. 2, certain diseases of the urinary system, such as left kidney stones, left ureteral stones, etc., patients often have symptoms of abdominal pain. The pain is characterized by more intense, mostly colic, sometimes accompanied by symptoms of hematuria, which can be diagnosed by doing ultrasound examination of kidney and ureter.3. Female patients are also seen with gynecological diseases, such as left-sided tubal inflammation, left ovarian cyst, pelvic inflammatory disease, etc., which can be diagnosed by doing ultrasound examination of ovary and fallopian tube. If symptoms of vague pain in the left lower abdomen appear, it is recommended to go to the relevant department of the hospital for examination in a timely manner.