PROBLEM TO BE SOLVED: To obtain a culture medium capable of cultivating mushrooms represented by Agaricus Blazei Murill and hard to cultivate and to provide a method for extracting an essence preservable for a long period from a dried material of the Agaricus Blazei Murill cultivated by using the culture medium. SOLUTION: Agaricus Blazei Murill is cultivated by using a culture medium for cultivating mushrooms comprising a Sasa albo-marginata essence, a pineapple enzyme and a bat guano. A dried material of the Agaricus Blazei Murill thus obtained is placed in a container and watered and the essence of the Agaricus Blazei Murill is boiled down until the amount of the added water attains about 35-65% based on the original amount under aeration. The essence is then extracted at 100 deg.C by stopping the aeration.
