Abstract: The dry weight, growth rate, nutrient content and enzyme activity of Stropharia rugoso-annulata mycelium were determined to reveal effect of magnetized water liquid fermentation on growth characteristics of Stropharia rugoso-annulata mycelium.Results showed that magnetized water culture could improve the dry weight, growth rate, nutrient content and enzyme activity of Stropharia rugoso-annulata mycelium.And the optimum magnetic field strength was 0.3 T which growth stable period was advanced 36 h, growth rate and biomass was improved by 27.64%, and 27.44% respectively, contents of soluble proteins, polysaccharides and cellulose was improved 1.34%, 28.08%, and 34.74% respectively, activities of protease, amylase, carboxymethyl cellulose, laccase and polyphenol oxidase were increased by 14.08%, 21.42%, 17.13%, 19.62%, and 19.33%respectively.Magnetic water could shorten the culture period, improving the yield and quality of Stropharia rugoso-annulata strains significantly.