The most likely causes of men’s urethral orifice pus: 1, gonorrhea, when unclean sexual intercourse infected with streptococcus, can appear the urethral orifice pus, outflow of yellow purulent discharge, accompanied by frequent urination, urinary urgency, painful urination symptoms, which is typical of gonorrhea performance. If a patient has a history of unclean sexual contact and has similar symptoms, it is recommended that a smear of gonococcus or a culture test of gonococcus be taken from the yellow pus at the hospital. If the culture or smear test confirms the diagnosis, it is recommended that active treatment, such as no treatment, later may be the sequelae of urethral stricture and other complications, treatment can choose ceftriaxone sodium intravenous injection. 2, non-gonococcal urethritis, common after mycoplasma, chlamydia or other atypical bacterial infection, can also appear urethral orifice outflow yellow purulent discharge light. This kind of yellow purulent discharge is relatively thin, the amount is relatively small, sometimes only in the underwear to see the yellow crust, more accompanied by itching in the urethra or urinary discomfort symptoms. It is recommended to retain the discharge for mycoplasma and chlamydia culture, culture mycoplasma and chlamydia, it is recommended to use macrolide antibiotics for treatment, such as erythromycin, roxithromycin, etc.