The average penis of a 14-year-old boy is 2.5-3.3cm, and a 14-year-old child has already entered the stage of puberty. Puberty is a very critical period from childhood to adulthood, in which the hypothalamus-pituitary-gonadal axis appears in a state of excitement, resulting in the secretion of sex hormones, which are expressed at this time in the development of sexual characteristics and sex organs. Generally speaking, boys from 11-12 years of age began to enter puberty, puberty is divided into five stages, the first of which is the pre-puberty, generally at the age of 11-12 years old, 13-15 years old is into the early puberty, that is, now said 14-year-old boy in addition to the development of the penis, the volume of the scrotum also began to increase, generally to 4-8 ml, and there is also the state of pubic hair is thin and straight, located at the root of the penis. Later is the middle puberty, late puberty and late puberty, generally to puberty in the state of the end of 18 years of age or so when the child’s overall sexual characteristics have been with the adult basically the same, so pay attention to the child’s sexual development, this period of time if there is an abnormality, must go to the hospital in a timely manner with the doctor to diagnose, clear the child is not the emergence of any abnormal situation.