The possible causes of urinary distension but not much urine: 1, urinary tract infection, infection after the urethral bladder mucosa epithelium appears congestion, edema and other changes. At this time, the sensitivity of the mucous membrane of the urinary bladder is increased, and the storage of a small amount of urine can produce strong stimulation and a sense of holding urine, there will be urinary distension. However, because the volume of urine is too small, not much urine is discharged during urination, and it is accompanied by urinary urgency and pain in the urethra. It is necessary to carry out routine urine examination and urine culture examination, and give anti-infection treatment after diagnosis. 2. The presence of irritating lesions in the bladder or urethra, such as bladder stones, urethral stones or bladder tumors, can produce local mucosal irritation and lead to a feeling of holding urine or urinary distension. In this case, it is not the increase of urine that stimulates the feeling of holding urine, so the urine volume is not much when urinating, and sometimes there may even be bright red urine or blood in the urine color. Ultrasound examination of the urinary system is needed to confirm the diagnosis, and if there are stones or tumors, surgery is required.