PROBLEM TO BE SOLVED: To obtain an unsterilized culture solution composition and to provide a method for cultivating mushrooms by using the composition. SOLUTION: This composition contains 56.4-62.4 wt.% of granite porphyry, 17.1-18.9 wt.% of calcium, 8.7-9.6 wt.% of a burnt ash of newsprint paper, 4.4-4.8 wt.% of a burnt ash of chaff, 2.2-2.4 wt.% of sugar, 1.3-1.5 wt.% of slaked lime, 1.71-1.89 wt.% of burnt pine needles, 1.3-1.5 wt.% of a charcoal of Quercus acutissima, 0.58-0.67 wt.% of a salt, 0.48-0.53 wt.% of burnt rice straws, 0.26-0.28 wt.% of burnt tobacco leaves, 0.26-0.28 wt.% of yellow soil and 0.17-0.19 wt.% of burnt garlics. The unsterilized culture solution composition is diluted to provide an unsterilized culture solution and a culture medium is then dipped in the resultant unsterilized culture solution to absorb the unsterilized culture solution in the culture medium. The culture medium is immediately bedded when the unsterilized culture solution is absorbed in the culture medium and mushroom spawns are inoculated into the culture medium and cultured.
