The invention relates to an extraction method and application of salt-tolerant yeast, the part of 5-10cm below unstirred soy sauce mash in a fermentation tank is used as a sample, a culture medium A and a culture medium B are prepared, the culture medium A comprises 1-10g of glucose, 0.1-2g of yeast powder, 0.1-1g of polypeptone, 0.1-2g of monopotassium phosphate, 1-8g of agar powder and 100g of water, the culture medium B is a mixture of raw soy sauce, salt and water, and the mixture is mixed with the raw soy sauce, the salt and the water. Uniformly mixing A and B, adding a sample to prepare a suspension, and performing plate separation and purification to obtain the salt-tolerant yeast; according to the method, the saccharomycetes are extracted, and after the saccharomycetes are subjected to enlarged culture, the generated alcohol is good in aroma, accompanied with special fragrant and sweet taste, and has discriminative taste; the salt-tolerant yeast is subjected to enlarged culture and added into soy sauce mash, and participates in the fermentation process as dominant bacteria, so that the beany flavor of the soy sauce can be effectively reduced, the special fragrance of the salt-tolerant yeast can enrich the flavor of the soy sauce, and the soy sauce has better discrimination than other soy sauce.