The size of the male penis varies. In the erect state, the length of the penis is about 9-15 cm and the diameter is about 2.5-4 cm, which is within the normal range. The penis in an erect state is much larger than in a weak state, and the size of the penis is affected by both congenital and acquired factors, with congenital factors meaning that the body is influenced by genetic factors that cannot be changed later in life. The congenital factor is that the body is rich in nutrients during youth development, more likely to promote the development of the penis, in daily life, if the penis can be normal urination or sex, it is a normal phenomenon, not related to the size of the penis. If the penis is short and even has an impact on sexual life or urinary function, immediately go to the hospital for a physical examination to see if there is a possibility of occult penis, and take good care of the penis in daily life, wash it regularly and keep it clean.