There are many diseases that occur with the onset of urinary closure, however each disease is different and can cause different harm to the patient, some of which can have very serious consequences. Mixing these diseases together can be dangerous and can cause great harm to the patient. Differential diagnosis of different diseases causing urinary closure: (1) caused by bladder or kidney tumor erosion with more bleeding forming clots blocking the urethra. Most of them are hemangiomas and malignant tumors (bladder cancer and kidney cancer), and most of them have a history of painless hematuria. However, there are some cases that occur for the first time and may disappear spontaneously and resume urination, which is often mistakenly thought to be “cured” by patients. The first time a painless hematuria occurs, it can disappear naturally and resume urination. The first is frequent urination at night, gradually developing into more frequent urination during the day, the urine flow becomes thin, the flow is slow and weak. Drinking alcohol, exertion, and cold are common triggers for difficult urination, hematuria, and massive retention of bladder urine. Ultrasound examination is not only simple and painless, but also can accurately detect the extent of lesions, the presence of complications and early cancer, and provide a basis for formulating a reasonable treatment plan.