Swelling and pain in the penis after every sexual intercourse may be caused by penile injury, glansitis, urethritis, as well as other reasons such as allergies. 1. Penile injury: too strenuous movements during sexual intercourse or incorrect sexual position may or may lead to penile injury, the patient may experience penile swelling and pain. 2. Glansitis: Glansitis may be caused by microbial infection, friction, unclean foreskin and other factors. Patients will have edema of the glans skin mucosa, localized pain, erythema and other manifestations, so patients will have symptoms of swelling and pain in the penis after each sexual intercourse. 3. Urethritis: male urethritis may be caused by gonococcus, Chlamydia trachomatis, Trichomonas vaginalis and other pathogens. The patient will be manifested as painful urination, frequent urination, painful intercourse, urethral redness and swelling, and thus the patient will have a swollen and painful penis after each sexual intercourse. 4. Other: the use of poor-quality condoms during sexual intercourse may cause allergies, patients will have symptoms of penile swelling and pain. At the same time, the patient’s sexual intercourse time is too long, will make the penis is friction, will also make the local red and swollen. It is recommended that every time the patient after sexual intercourse, the penis is swollen and painful performance, need to promptly seek medical treatment, you can choose the appropriate measures under the guidance of the doctor treatment.