There is no uniform standard for normal penis length in China. The length and diameter of the penis of 283 men with normal fertility under non-erectile conditions were measured, and the length of the penis from the pubic surface of the lower abdominal wall to the head of the penis ranged from 4 to 12 cm, while the diameter of the lower coronal groove of the penis ranged from 2.1 to 3.2 cm. The Shanghai Family Planning Institute has measured 900 cases of newly married men, the maximum penis length in the erect state is 16 cm, the minimum 6 cm, the average 11.6 ± 1.7 cm; the maximum diameter is 5.2 cm, the minimum 2.2 cm, the average 3.3 ± 0.4 cm. Of course, penis length and thickness are affected by factors such as height, physique, hormone levels, development, and different levels of blood filling at the time of measurement, and the measurement results vary greatly from person to person. It is important to emphasize that the length and thickness of the penis and sexual function, sexual life satisfaction, etc. is not completely proportional, as long as there is a normal erection, the couple is satisfied with sex life, in fact, it is not necessary to care about the length and thickness of the penis.