The left lower abdominal pain and normal stool can be seen in the colon disease, urinary tract disease, reproductive system diseases. 1. Colon diseases: such as inflammation of the sigmoid colon, tumors, diverticulitis and other diseases, stimulation of the intestinal wall of the left lower abdomen can appear in the left lower abdomen hidden pain and normal stool. 2. Urological diseases: such as stones in the left kidney and ureter, inflammation, varicocele, etc., can be manifested as vague pain in the left lower abdomen, which may be accompanied by nausea and vomiting. Inflammation of the kidneys and ureter can be accompanied by frequent urination, urinary urgency and urinary pain. 3. Reproductive diseases: such as female pelvic inflammatory disease, ovarian cyst torsion, left ovarian rupture, left tubal inflammation, ectopic pregnancy rupture, and male prostatitis and other diseases, may appear in the left lower abdominal pain, usually no stool abnormalities. Chronic pelvic inflammatory disease may also be accompanied by discomfort in the lower abdomen. In addition to the above mentioned organs located in the left lower abdomen, there are also considerations of neighboring organs and systemic diseases, if the patient left lower abdominal pain, or accompanied by other symptoms, it is recommended to consult a doctor in a timely manner, improve the abdominal ultrasound, gastroenteroscopy, abdominal CT and other examinations, under the guidance of the doctor to determine the cause of the disease, and active treatment, to avoid delayed condition.