The erection of the penis is mainly achieved by the filling of the penile corpus cavernosum, the anterior part of which protrudes outside the body, that is, the part of the penis that we can see, while the posterior part of which is quite large in the body, is located below the pubic symphysis, and the deepest part is fixed by the two penile corpus cavernosum feet respectively in the bilateral pubic symphysis branches, and the penile corpus cavernosum relies on the The penile corpus cavernosum relies on the superficial penile suspensory ligament and the deep penile suspensory ligament fixed in front of and below the pubic symphysis, and it is due to the existence of these ligaments that the length of the exposed penis is maintained basically constant. When the ligaments are surgically severed, a portion of the penile corpus cavernosum, which was fixed to the pubic bone, will be released and protrude out of the body, thus increasing the length of the penis. This is the basic principle of penis lengthening surgery. Indications for penile lengthening surgery: 1, penile dysplasia; 2, congenital micropenis: its penis length is less than 5cm when weak, erect length is less than 10cm can not meet the sexual requirements of the female; 3, penile cancer after partial penectomy; 4, other such as: the penis is slightly small or basically normal after erection, but the patient psychological barriers or even affect normal sex life; 5, accompanied by penile venous fistula impotence, as Penile ligation of deep and superficial veins of the dorsal penis at the same time for penile lengthening, often can achieve better results; 6, occult penis can be done at the same time penile lengthening when doing penile plastic surgery.