Fifteen-year-old boy beard grows black is a normal physiological phenomenon, if the beard affects the daily life, can be removed. Boys enter puberty at the age of fifteen, the body began to secrete androgen, it will stimulate the development of the boy’s secondary sexual characteristics, long beard belongs to the male secondary sexual characteristics, this is a normal phenomenon. Due to individual differences, the color and amount of beard will be different, so don’t worry. Because of the individual differences of each person, if the fifteen-year-old boy’s beard is longer, you can properly shave, but it is not recommended to frequently shave. If shaving, it is recommended not to use a razor blade to scrape, so as not to cut the child’s skin, it is best to use an electric razor to scrape, it is safer and more convenient. Fifteen-year-old boy beard grows black is a sign that the boy grows up, need to be treated correctly. If necessary, you can go to the hospital and consult a professional doctor.