Normal penis length is how much the domestic has not been standardized. The length and diameter of the penis of 283 men with normal fertility in the non-erectile condition have been measured, and the length of the penis from the pubic bone surface of the lower abdominal wall to the head of the penis ranges from 4 to 12 centimeters, while the diameter of the lower part of the coronal groove of the penis ranges from 2.1 to 3.2 centimeters. The Shanghai Municipal Family Planning Institute has measured 900 cases of newly married men, the maximum length of the penis in the erect state is 16 centimeters, the minimum 6 centimeters, an average of 11.6 ± 1.7 centimeters; the maximum diameter of 5.2 centimeters, the minimum 2.2 centimeters, an average of 3.3 ± 0.4 centimeters. Of course, the length and thickness of the penis is affected by factors such as height, physical fitness, hormone levels, development, and different degrees of engorgement at the time of measurement, and the measurement results vary greatly from person to person. It should be emphasized that the length and thickness of the penis and sexual function, sexual life satisfaction and so on is not completely proportional, as long as there is a normal erection, the husband and wife are satisfied with the sex life, in fact, do not have to care about the length and thickness of the penis.