The redness of the male glans with itching after sex is caused by glansitis of the foreskin, leading to this situation consider two problems: one, the woman may suffer from gynecological inflammation, such as mycobacterial vaginitis, through sexual life infection to the male partner. Two, the male partner may be too long foreskin, do not pay attention to hygiene, after the friction of sexual life, can lead to inflammation of the glans foreskin. When there is inflammation of the glans and foreskin both sides need to go to the hospital for examination, the male can go to the urology department to find a specialist physician for physical examination, the female to the hospital gynecology department for physical examination, there are problems both sides need to actively carry out treatment. It is important to pay attention to the hygiene of the external genitalia, especially the hygiene of sexual life, before and after sex to wash the external genitalia, it is best to wear condoms.