In this work, we suggest procedure for manufacturing of highly pure schizophyllan (SPG) cleaved into shorter fragments by ultrasonication. The ultrasonicated SPG (uSPG) was prepared from Schizophyllum commune submerged cultivation in bioreactor, culture broth ultrasonication with 100 Ws/mL energy input, followed by depth filtration and ultrafiltration. The uSPG contained less than 0.3%w/w protein and 0.078 IU/mg endotoxin. Chemical composition and structure of the uSPG were analyzed by GC and NMR, and conformation of the molecules was documented by AFM. Apyrogenicity of uSPG was proved by MAT test. Immunomodulatory properties of native and denatured uSPG were studied in vitro with human whole blood. The LPS-spiked samples revealed immunomodulatory activity of both native and denatured uSPG. Protein array showed that native uSPG activates certain cytokines and chemokines significantly stronger than denatured uSPG.