PROBLEM TO BE SOLVED: To provide an artificial culture medium for mushroom, capable of rapidly increasing the yield of mushroom in comparison with conventional log cultivation having a long cultivation period and harvest apt to be influenced by a weather condition, and conventional mushroom bed artificial cultivation having low yield and a long cultivation period, and to provide an artificial cultivation method for mushroom using the culture medium. SOLUTION: This artificial culture medium for mushroom comprises calcium aluminate tricarbonate hydrate. The artificial cultivation method for mushroom comprises using the artificial culture medium.