On October 29, the Department of Urology successfully performed bladder enlargement for a female patient. The patient had been urinating urgently and frequently for 5 years, and had been to many big hospitals all over the country, and came to our hospital for medical treatment after various methods of treatment but with unsatisfactory results. The patient urinated once every few minutes, with small amount of urine each time, severe pain in holding urine, and unbearable pain in the lower abdomen, urethra and perineum when she felt the urge to urinate. After admission, cystoscopy, urodynamics, CT and other examinations revealed that the bladder capacity was 75 ml, which was significantly reduced, and the bladder mucosa was stiff, fibrotic and poorly elastic. The diagnosis was bladder contracture: the patient had a long history of interstitial cystitis, severe fibrosis of the bladder wall, and shrinkage of the bladder capacity, resulting in frequent urination. In order to improve the patient’s quality of life,and to improve bladder function,bladder enlargement was performed as the most effective treatment. During the operation, 15cm of sigmoid colon was taken to make a new bladder, which was anastomosed with the original bladder to enlarge the bladder capacity. Patient Currently the patient has recovered and was discharged from the hospital. This is a typical case of bladder contracture. The common causes of bladder contracture are various inflammatory lesions of the bladder, such as tuberculous cystitis, interstitial cystitis, and radiation cystitis. These diseases. Often, the healing process of inflammation causes tissue fibrosis, resulting in shrinkage of the bladder.