The change of voice in boys is one of the signs of puberty, and it is generally considered normal for boys to start puberty between the ages of 9 and 14. If a boy has testicular enlargement, growth of axillary and pubic hair, thickening of voice, growth of beard and even ejaculation before the age of nine, it is considered precocious puberty, but if at the age of 14, testicular enlargement, sudden growth of pubic and axillary hair, growth of voice and beard are still absent, it is called delayed puberty. This is the time to come to the hospital for a thorough examination and evaluation. Whether it is precocious puberty or delayed puberty, it is necessary to go to the hospital and visit the endocrinology department to further evaluate whether it is a physical delay in puberty or whether there are other pathological causes. If there is a pathological cause, it may be too late for treatment if the cause is detected in time. Otherwise, if it is precocious puberty, the best time for height growth may be missed.