A circle of small bumps under the glans may be caused by pearly papules, condyloma acuminatum, genital herpes, sebaceous ectasia and other reasons. 1. pearly papules: due to pubic moisture, long foreskin, poor local hygiene, inflammation stimulation and other reasons, resulting in a circle of small bumps under the glans, usually manifested as white, yellow or reddish pimples. 2. Condyloma acuminatum: caused by human papillomavirus infection, patients may show single or multiple reddish bumps under the glans, accompanied by tingling, itching and other symptoms. 3. Genital herpes: caused by herpes simplex virus infection, low immunity, etc., patients may present with small bumps under the glans, which may be accompanied by tingling, itching, burning and other symptoms. 4. Sebaceous gland ectasia: small bumps under the glans may also be a physiological variant of sebaceous gland development, usually manifested as small yellowish-white pimples of the size of a pinhead to a corn. A circle of small bumps under the glans may also be caused by other reasons, it is recommended that the patient timely consultation and examination, clear the cause of the disease to comply with the doctor’s instructions standardized treatment.