The thickening and hardening of the urethra is caused by urethral tumors. The cause of urethral tumor is not clear, but it may be related to sexual intercourse, menstrual paper friction, birth injury, urethral infection and certain pre-existing vulvar lesions such as mucosal leukoplakia, urethral caruncle, urethral polyps, chronic urethritis, urethral stricture and repeated urethral dilatation. The cause of urethral tumor is not clear, but it may be related to stimulation of sexual intercourse, friction of menstrual paper, birth injury, urethral infection and certain pre-existing vulvar lesions such as mucosal leukoplakia, urethral caruncle, urethral polyp, chronic urethritis, urethral stricture and recurrent urethral dilatation, etc. The age of onset is mostly between 40 and 60 years. The following diseases are also causes of urethral thickening and hardening: 1. Urethral injury Urethral injury is a common injury to the urinary system, occurring mostly in men and mostly in young adults, especially in the more fixed bulb or membrane. The male urethra is divided by the urogenital diaphragm into the anterior urethra (bulb urethra and overhanging urethra) and the posterior urethra (prostate urethra and membrane urethra). Urethral injury can lead to infection, stricture, obstruction and sexual dysfunction if not treated properly. 2, urethral caruncle Urethral caruncle is a common urethral disease in women, mainly manifested as benign polyp-like masses at the urethra. Also known as urethral granuloma or vascular polyp. Its occurrence may be related to chronic inflammation or chronic irritation of the vulva, severely reduced estrogen levels, local submucosal varicose veins, and urethral mucosal prolapse and ectropion. 3, urethral stones Urethral stones are not common in clinical practice. Most of them come from the bladder and the urinary system above the bladder, such as kidney stones, ureteral stones or bladder stones. Stones may remain in the urethra or become lodged in the prostatic urethra, navicular fossa, or external urethral orifice during discharge. Rarely, they are secondary to urethral strictures, urethral atresia, foreign bodies, or urethral diverticula. Stones originating in the urethra are quite rare. They are usually solitary stones. Most of the stones with co-infection are composed of ammonium magnesium phosphate. In women, the majority of urethral stones occur within the urethral diverticulum.