Left-sided abdominal pain may be caused by ureteral stones, left-sided adnexitis, inflammatory bowel disease and other conditions. 1. Ureteral stone: If the stone is too large and enters the left ureter, it may scratch the urethral mucosa or become embedded and block the ureter, causing left abdominal pain. Acute ultrasonic lithotripsy and other auxiliary treatments are needed when necessary. 2. Left-sided adnexitis: women do not pay attention to hygiene during menstruation, lower reproductive tract inflammatory infections such as upward leading to inflammation of the left adnexa, inflammation stimulation of the surrounding tissues often appear in the left side of the abdominal pain manifestations. 3. Inflammatory bowel disease: ulcerative colitis or Crohn’s disease may cause left-sided abdominal pain, which can involve the left side of the colon. In the acute stage is mainly accompanied by diarrhea, fever and other manifestations. It is necessary to improve the colonoscopy, under the guidance of the doctor oral 5-aminosalicylic acid preparations, glucocorticoid drugs to assist in the treatment. 4. Enteritis: can be caused by bacteria, viruses, parasites and other causes of inflammation in the descending colon area, the active phase of the disease will cause intestinal mucosal epithelium congestion, edema, will stimulate the intestinal tract to produce the left side of the abdominal pain. Antibiotics or antiviral drugs can be used to treat the condition. If the left side of the abdominal pain persists without relief, it is recommended to consult a doctor in time, complete colonoscopy and gynecological examination, etc., with the help of the doctor to clarify the cause, and carry out targeted treatment or therapy.