In general, it is normal for a 10-year-old boy to grow a beard. In general boys before the age of 9 years old appeared secondary sexual characteristics development, such as long beard, throat knot, testicular enlargement, etc., consider the possibility of precocious puberty. But 10-year-old boys appear to grow a beard, not be judged as the scope of precocious puberty, mostly normal physiological phenomenon. Beard belongs to the secondary sexual characteristics, will appear when the boy enters puberty. If the child grows a beard earlier, it may be due to genetic factors or environmental causes, if not accompanied by other uncomfortable symptoms, are normal phenomena, do not worry too much. You can also go to the regular hospital to do some relevant examinations, such as bone age, sex hormone levels or gonad ultrasound. If there are no abnormal indicators through the above examinations, it means that the child is under normal physiological development and does not have the symptoms of precocious puberty.