The following diseases should be considered: 1. urinary stones, manifested as left lower abdominal cramps, pain dispersion to the perineum, and often lumbar pain and discomfort. 2. colorectal tumors, mainly even colon cancer and rectal cancer. In addition to pain in the left abdomen, diarrhea, blood in stool, poor nutrition, weight loss and a feeling of urgency, patients should improve colonoscopy and tumor marker examination. 3. If female patients, they should consider adnexal diseases, such as adnexitis, adnexal tumor and so on. Therefore, if there is often pain in the left lower abdomen, the patient’s condition should be analyzed comprehensively, and according to the results of the analysis, how to examine and treat.