A little bit of swelling after the foreskin is turned up may be caused by foreskin inlay, foreskin inflammation, friction. 1. Foreskin ingrown: some people have narrow opening of the foreskin, after the foreskin is turned up, the narrow position of the foreskin will be stuck on the penis, resulting in local lymphatic drainage obstacles and thus edema. Generally, the swelling will gradually subside after the foreskin is reset. 2. Inflammation of the foreskin: If the foreskin is infected by pathogenic microorganisms after turning it over, it will also lead to edema, and some of the patients will also be accompanied by pain, or even ulceration and pus. Need to actively anti-infection treatment. 3. Friction: after turning the foreskin to reveal the inner plate of the foreskin, due to the inner plate is more tender and underwear friction is also prone to edema. Overall, the foreskin edema need to pay attention to, go to the hospital in a timely manner to check, clear causes under the guidance of the doctor for targeted treatment.