Deer horn has been used in oriental medicine and folk remedy. It has had much effects on `health and tonic efficacy`. But this word, `health and tonic efficacy`, is very obscure in modern sense. This report attempts to investigate their scientific and objective effects among many papers. The biochemical components of antler are composed of pentoses, hexoses, acid mucopolys-accharides, free and ester fatty acids, glycolipids, phospholipids, prostaglandins, sterols, protein and peptides, free amino acids, minerals, hormones etc. Deer horn extract especially increases body weight gain and feed efficiency, and it stimulates the ability of spermatogenesis of animal. However, a few papers have reported concerning the toxicity and side effects of antler.