The red glans and swollen foreskin is not necessarily a sexually transmitted disease (STD). Physiological factors such as excessive friction, irritation, and other diseases such as torticollis and gonorrhea can be considered, and further examination is recommended. 1. Physiological factors: if there is excessive masturbation or sex too often and other physical friction, or the application of exogenous drugs and other chemical stimuli may cause redness and swelling of the glans and foreskin. 2. Circumcision and glansitis: for those who are circumcised or circumcised, if they don’t pay attention to personal hygiene, it may lead to the accumulation of foreskin scale, and long-term stimulation will cause circumcision and glansitis, resulting in redness and swelling of the foreskin and glans. 3. Sexually transmitted diseases: If the redness and swelling of the foreskin and glans occurs after unclean sex, gonococcal infection and other sexually transmitted diseases can be considered. Therefore, it is recommended to go to the hospital in time for further examination and clear diagnosis.