Height not only affects a person’s external image, but also directly affects future marriage and employment, especially for men, the reason is that the current gender imbalance in our country, fewer girls. If you don’t have an upright body, marriage is a problem. Therefore, as a boy now, especially concerned about the height of the problem, but also want to know how many years old boys will stop growing taller, so as to have a psychological preparation. To understand this issue, it is necessary to know how people grow taller. Human height depends mainly on the length of the long bones (such as the femur and tibia of the lower limbs). The growth of long bones includes the longitudinal growth of bones (i.e., linear growth) and the maturation of bones in two aspects: a. At birth, the main long bones, such as the humerus, femur, and both ends of the tibia epiphysis, except for the distal end of the femur, are cartilage, and later, at different ages, the epiphysis appears as an ossification center, which gradually increases in size, and bone tissue replaces cartilage tissue. However, there is still a section of cartilage between the diaphysis and the epiphysis, which is medically called epiphyseal cartilage, and the cartilage cells in this section keep dividing and multiplying longitudinally to generate new cartilage during the growth and development period, and at the same time, the osteogenesis process is also going on in the part near the diaphysis. Second, the long bones grow little by little, and people grow taller gradually, but at the age of 20-22, the epiphyseal plate cartilage gradually disappears, the epiphysis closes, the longitudinal growth of bone stops, and people can no longer grow taller. However, because the physical development conditions of girls and men are somewhat different, generally at the age of 20 for girls and 22 for boys, height growth basically stops. But some people have found that as long as the boy has not reached the age of 25, then there is still the possibility of continuing to grow taller, but the speed of development is significantly slower, and the height increase is less obvious.