A lump in the foreskin of the penis may be related to circumcision, warts, genital herpes, sebaceous cysts and other causes. 1. Circumcision: it is the most common cause of bumps in the foreskin, which is commonly found in patients with prolonged foreskin or phimosis. 1. Condyloma acuminatum: if the penile foreskin is infected by human papilloma virus, wart-like cumbersome organisms can appear, manifested as bumps at the penile foreskin. 2. Genital herpes: caused by herpes simplex virus infection, there can be a pimple in the foreskin of the penis, which may be accompanied by pain. 3. Sebaceous cysts: If the sebaceous gland secretions are not discharged properly from the follicular opening, cysts can form. It is recommended that people with a lump in the foreskin of the penis go to the hospital in a timely manner to clarify the cause of the disease, under the guidance of the doctor for standardized treatment, so as to avoid delays in the condition.