Hidden pain in the left lower corner of the abdomen may be caused by colitis, proctitis, constipation and so on. 1. colitis: due to bacterial infection or eat unclean food, autoimmune reaction caused by abnormal inflammatory reaction of the colon, inflammation continues to stimulate, resulting in lesions diffuse congestion, edema, erosion, ulceration, etc., diet is not when the colon will spasm, resulting in the lower left corner of the abdomen hidden pain. 2. Proctitis: due to improper diet, it is easy to induce rectal inflammation reaction, inflammatory stimuli will cause rectal spasm, there will be the phenomenon of the left lower corner of the abdomen, accompanied by abdominal distension, diarrhea, and other symptoms, exhaust defecation can be relieved. 3. Constipation: constipation will lead to stool can not be discharged in time, the accumulation of the intestine, will cause the left lower corner of the abdomen hidden pain. If the phenomenon of the left lower corner of the abdomen hidden pain, it is recommended to go to the hospital as soon as possible, according to the specific circumstances, under the guidance of the doctor, actively cooperate with the treatment.