White blisters under the foreskin may be the result of diseases such as condyloma acuminatum, glans, and genital herpes. 1. Condyloma acuminatum: This disease is caused by the human papilloma virus and is almost always transmitted through sexual contact. Common risk factors include multiple sexual partners and unsafe sex. Generally there are no symptoms in the early stage of the disease, with the further development of the disease, the male patient’s glans, the prepuce tie and other places will appear white, pink and other colors of pimples, manifested as corns, cauliflower, etc., and there will also be pain, itching, foreign body sensation and other symptoms. 2. Glans: This disease is mainly caused by the infection of pathogenic bacteria such as Candida, anaerobic bacteria, Staphylococcus aureus and so on. Secondly, it may also be caused by irritation of urine, condoms and other substances. In the case of circumferential ulcerative glans penis, the patient will have erythema, edema, white papules and other symptoms at the glans. 3. Genital herpes: The causative agent of the disease is herpes simplex virus, which can be transmitted through sexual contact and mother-to-child transmission. Most patients do not have any signs and symptoms. When clinical symptoms appear, there will be clusters of small blisters, itching and pain in the coronal groove, foreskin and glans of male patients. There are many causes of white blisters under the foreskin, and it is necessary to go to the hospital to clarify the specific causes.