Abdominal pain and frequent diarrhea may be caused by abdominal cold, irritable bowel syndrome, acute gastroenteritis, ulcerative colitis and other reasons. 1. Abdominal cold: do not pay attention to abdominal warmth or eat cold food, abdominal cold caused by intestinal smooth muscle contraction spasm, abdominal pain, intestinal peristalsis faster cause frequent diarrhea. 2. Irritable Bowel Syndrome (IBS): high pressure from study or work, frequent anxiety and depression, leading to gastrointestinal autonomic nerve disorders, triggering irritable bowel syndrome, causing abdominal pain and frequent diarrhea. 3. Acute gastroenteritis: Eating spoiled food, food infected by bacteria, etc. triggers acute gastrointestinal inflammation, resulting in abdominal pain and frequent diarrhea, nausea, vomiting and other symptoms. 4. Ulcerative colitis: in the acute stage, it mainly manifests as abdominal pain, frequent diarrhea, pus and blood stools with mucus, etc. The combination of clinical manifestations and colonoscopy endoscopy can make a clear diagnosis. Abdominal pain and frequent diarrhea, there may be other causes, it is recommended to seek medical advice as soon as possible, and follow the doctor’s instructions for treatment.