Urine erythrocytes 25/ul, indicating the presence of microscopic hematuria, may be physiological factors, acute injury, urinary tract infection, urinary stones, urinary tract tumors and other factors. 1. Physiological factors: such as menstrual blood contamination of urine or some strenuous exercise, can lead to microscopic hematuria, can return to normal on their own, do not need special treatment. 2. Acute injury: such as external blows, resulting in localized damage to the urethra, a small amount of blood into the urine, will lead to microscopic hematuria, accompanied by urethral pain and other symptoms. 3. Urinary system infection: for example, urethritis, cystitis, due to the presence of infectious factors, may lead to damage to the urethra or bladder, it will cause microscopic hematuria, accompanied by frequent urination, urinary urgency, urinary pain and other symptoms. 4. Urinary stones: for example, bladder stones, some exercise or urination, the stone on the bladder caused by irritation, causing bleeding, will lead to microscopic hematuria, accompanied by urinary difficulties, painful urination and other symptoms. 5. Urinary system tumor: for example, bladder tumor or urethral tumor, tumor surface tissue necrosis, causing bleeding, which will cause microscopic hematuria, and in severe cases, hematuria will be visible to the naked eye. Urine erythrocytes 25/ul, and there are other abnormal manifestations, excluding physiological factors, it is recommended to go to the hospital urology department for appropriate examination and treatment to avoid aggravation of the lesions.