The unclean urine after urination may be due to diseases such as urethritis, cystitis and chronic prostatitis. 1. Urethritis: usually due to gonococcal and non-gonococcal infections, and also related to age, direct transmission, indirect transmission and other factors. The general gonococcal urethritis patients often appear urinary frequency, urinary urgency, urinary pain and other symptoms, also accompanied by urethral urethral urethral redness, swelling, urethral pus secretion, etc., if it is a non-gonococcal urethritis, there can also be an increase in urethral secretion, can be manifested in the urinal after the residual urine is not clean. 2. Cystitis: usually due to bacterial infection, may also be due to foreign bodies, drugs, chemicals and other conditions, but also with the obstruction of urinary flow, immune deficiency and other factors. Patients often appear urinary frequency, urinary urgency, urinary pain and other symptoms, can also be accompanied by urethral burning sensation, serious cases can also appear incontinence, so that there is a residual urine after urination is not clean. 3. Chronic prostatitis: the cause is more complex, usually due to chlamydia, mycoplasma infection, and also abnormal immune response, urine stimulation and other factors. Patients often appear pelvic area pain, urinary frequency, urinary pain, urinary sensation, some patients can be manifested as urine after urination, and can also be accompanied by blood sperm, hematuria and other phenomena. In addition, older men urinary incontinence is most commonly associated with prostate hyperplasia. It is recommended that when the phenomenon of residual urine after urination is not clean, the cause of the disease should be clarified in a timely manner and reasonable treatment should be carried out.