Boys 18 years old may still grow taller, but whether they can grow taller depends mainly on the degree of epiphyseal closure, if the bone line is basically closed, generally will not grow taller, but due to individual differences, there are many factors affecting height, can not be generalized. The human body’s height growth generally has two periods, one is before the age of two, the other period for puberty, will be affected by nutrition, exercise, genetics and other factors, 18-year-old boys if the daily diet is more regular, nutrition is healthier, if the epiphysis has not yet closed, coupled with good exercise and adequate sleep, height growth will be more rapid, may continue to grow. But most of the boys after 18 years old sexual function gradually mature, epiphysis basically closed, height basically will not continue to grow, so daily to maintain a good diet and work and rest habits, appropriate exercise and increase nutrition, can help the growth of height.