Sometimes the urethra stings when urinating, then the possible causes: first, urethritis, can appear local mucous membrane edema, broken and other changes, urine flow into the relevant inflammation of the mucous membrane, it will produce stinging sensation, need to carry out routine urine examination to determine the infection and give anti-infection treatment; second, the presence of urinary system stones, after lithotripsy or drug de-stoning and other treatment, the discharge of stones can appear a transient urethral Third, if the concentration of urine is too high and some crystalline material is oversaturated, there will be transient stinging pain in urination, mostly manifested as white urine or cloudy urine, and this phenomenon will disappear after drinking more water. It is recommended that a routine urine test be performed to further exclude.