The invention discloses a mushroom soup and a cooking method thereof. The raw mateirals of the mushroom soup include chanterelle, toadstool, fungus suillus, chanterelle, boletus erythropus, sarcodon aspratum, bamboo fungus, gloeostereum insarnatum, tricholoma matsutake, tremella auramtialba, club fungi, cepe, hericium erinaceus, pleurotus eryngii, gomphidius rutilus, cordyceps sinensis, helvella elastica and flammulina velutipes. The cooking method comprises the following steps: soaking the raw materials, heating for more than three hours under big fire, wherein during the heating process, the soup is stirred uniformly for many times and floating foams on the surface are removed in time; after foam is removed, further heating under soft fire, wherein the soap is stirred for many times during the heating process; stopping heating, covering with a cover, standing for precipitation, thus obtaining the mixed mushroom soup. In the raw materials, the mushrooms are matched scientifically and reasonably, thus the mushroom soup is suitable for various people. In the cooking method, characteristics of various mushrooms are put into a full play, the taste and the fragrance components are mixed together, the nutrition and the taste are the best, and the mushroom soup has extremely high northern regional features, specific mushroom smell is kept, the efficacies of improving the immunity and the like are achieved, and the mushroom soup is suitable for people with various physiques.