It is possible for a boy to grow up to 175cm after 155cm voice change. Voice change is only one of the phenomena of the development and maturation of secondary sexual characteristics, and height growth is not directly related; height growth is related to genetics, nutrition, sleep and exercise. 1. Heredity: Half of a child’s genes come from the father and half from the mother, so generally the height of the father and mother has an effect on the height growth of the child. 2. Nutrition: In the process of height growth, bone development is particularly important, and calcium and vitamin D are the most important factors in bone development. 3. Sleep: During the night sleep, the body will secrete growth hormone that promotes the growth and development of the body, which is conducive to height growth. 4. Exercise: Exercise can promote blood circulation, strengthen the blood supply of bone cells and improve the proliferation of epiphyseal cartilage. After the change of voice, the height may still continue to grow 20~30cm, the change of voice is not an indicator to evaluate whether the height grows or not; in the process of the child’s growth and development in order to be taller, we should strengthen the nutrition, eat more protein-rich, vitamin-rich foods such as: eggs, lean meat, fish, milk, etc., and at the same time, we also need to develop a good sleeping habit and appropriate exercise. If the patient growth stagnation should be timely medical treatment, under the guidance of the doctor to identify the causes of active treatment.