Some small bumps on the foreskin for a long time may be caused by seborrheic dermatitis, flat warts, condyloma acuminatum, hair follicle infections and so on. 1. Seborrheic dermatitis. Seborrheic dermatitis occurs due to heredity, immune dysfunction and other reasons, resulting in the production of fat particles on the surface of the foreskin and the formation of small pimple-like changes, which are not accompanied by itching and pain. 2. Flat warts. Mainly caused by HPV (human papillomavirus) infection, resulting in the surface of the foreskin to produce nodule-like swelling. 3. Condyloma acuminatum. When the patient is sick, a cauliflower-like or papillary swelling is formed between the foreskin and the coronary groove, which is easy to bleed when touched and has a hard texture, while the acetic acid test is positive. 4. Hair follicle infection. Caused by bacterial infection and other reasons, resulting in localized boil changes, the patient’s foreskin skin appears acne-like changes. There may be other reasons for some small bumps on the foreskin, you should go to the hospital in time, and follow the doctor’s instructions for medication.