Men’s beard grows fast, mainly affected by genetic factors and androgen levels, the common clinical reasons are physiological androgen secretion, drugs, endocrine disorders and other reasons. 1. Physiological androgen secretion: the beard belongs to the male secondary sexual characteristics, when the androgen secretion in the normal human body is strong, the growth of the beard will be stimulated and rapid growth. Secondly, the body intake of nutrients is sufficient, beard parts have enough nutritional supply, which will also cause rapid growth of the beard, is a normal physiological phenomenon. 2. Pathological reasons: often stay up late or insomnia, mental stress, improper diet, the use of drugs, etc., will cause endocrine disorders, androgens may be relatively increased, resulting in rapid growth of beard. For people with adrenal tumors and other diseases, their bodies may have abnormal secretion of androgens, which can also cause rapid beard growth. If necessary, it is recommended to consult a doctor for a clear diagnosis and further treatment.