There is no standardized data on the length of a man’s penis, and in most cases it is considered normal if it reaches about 10 to 15 centimeters when erect. The length of a man’s penis is related to both genetic and acquired factors. Genetic factors cannot be interfered with, while acquired factors can be improved to a certain extent. During puberty, the first sex signs of men gradually develop and mature, and the size of the penis is basically fixed. If there is no abnormality in the development of the penis and foreskin before puberty, the length of the penis is probably normal in general. In China, the length of most men’s penises when erect is between 10 and 15 centimeters. If before puberty, there are conditions such as prepuce, hidden penis or abnormal hormone secretion, the development of penis size may be affected, and early medical intervention is needed to deal with it. If you notice any abnormalities in your penis, you need to seek prompt medical attention.