External reproduction refers to the external genitalia; the reproductive system of both males and females can be divided into internal and external genitalia; of these, the external genitalia are primarily the copulatory organs of the two sexes; the structure of the external genitalia is different in males and females. 1. Male external genitalia: consists of scrotum and penis; scrotum is a pouch-like structure located behind and below the penis; scrotum wall consists of skin and fleshy membrane, scrotal septum divides the scrotum into left and right chambers, and the chambers include testes, epididymis, vas deferens testicular department and other structures; penis is a sexually oriented organ, which is divided into the head, body, and root of the three parts, and is mainly made up of two penile spongiosa and one urethral spongy body. 2. Female external genitalia: that is, the female genitalia, including structures such as the mons pubis, labia majora, labia minora, vaginal vestibule, clitoris, vestibular bulb; the female genitalia is located between the two medial femurs, in front of the pubic symphysis, and behind the perineum. For patients with reproductive system diseases, they should immediately go to regular hospitals and be treated under the guidance of professional physicians to avoid delays.