The invention discloses edible fungus preservation liquid and a preparation method thereof; the edible fungus preservation liquid includes the raw materials (by weight percent) of 0.05%-0.1% of sodium acetate, 0.1%-0.2% of sodium chloride, 0.01%-0.03% of potassium sorbate, 0.02%-0.05% of ascorbic acid, 0.5% -3% of acidity pH regulator, 0.2%-2% of calcium preparation and 0.05% -0.1% of chitosan; the raw materials are dissolved in water. The invention is used for edible fungus preservation, is simple and easy for operation, is safe and hygiene and has good fresh keeping effect.