The present invention relates to a method of fermenting velvet antler (or venison or deer bone) together with a mushroom concentration in order to increase the efficacy thereof, and a fermentation product obtained thereby. In accordance with the present invention, velvet antler is fermented in a state in which it was not concentrated or ground, and the shape thereof is maintained after fermentation. Thus, the loss of velvet antler is insignificant, and the fermented velvet antler has a high efficacy and can be used in various shapes in subsequent processes.