The swelling of the glans and the flow of water may be gonorrheal urethritis, non-gonococcal urethritis, etc.; it may also be the flow of prostate fluid during sexual arousal. 1. Gonococcal urethritis: mainly caused by sexual contact. At the beginning of the infection, the patient’s urethra may be red, swollen and itchy. At the same time, the urethra will discharge a large amount of mucus or purulent secretions, there will be urinary discomfort. There may also be swelling of the penis, frequent urination, urinary urgency, pain in urination, and even the symptoms of hematuria. 2. Non-gonococcal urethritis: It is urethritis caused by infection by pathogenic bacteria other than gonococcus. Symptomatic patients may show an increase in urethral secretion, which is a white thin liquid; symptoms such as urethral tingling and painful urination may also occur. 3. Prostate fluid during sexual arousal: when boys are in a state of sexual arousal, they can secrete prostate fluid, which may also lead to swelling of the glans and outflow of watery fluid. Once the above symptoms appear, under the premise of not being able to relieve, should immediately go to the hospital, under the guidance of the doctor for standardized consultation.