Objective: In order to extract and utilize the umami compounds of Hypsizygus marmoreus fully， the effects of different protease treatments on the release of umami substances in the pileus and stipe of Hypsizygus marmoreus were studied. Methods: Three single-protease (flavourzyme， protamex， papain) and two double-protease (protamex/flavourzyme， papain/flavourzyme) were used to hydrolyze the pileus and stipe of Hypsizygus marmoreus. Then， the changes on the release of umami compounds in the pileus and stipe of Hypsizygus marmoreus treated with five protease groups were analyzed. Results: Enzymatic treatment by protamex/flavourzyme showed the highest level of umami amino acids and umami nucleotides(P＜0.05). The contents of umami amino acids and umami nucleotides were 20.85 mg/g and 10.06 mg/g， 8.45 mg/g and 3.88 mg/g in the pileus and stipeafter hydrolysis by protamex/flavourzyme. Therefore， the equivalent umami concentration of pileus was significantly increased from the second grade(836.90 g MSG/100 g) to the first grade(1 333.75 g MSG/100 g) after hydrolysis byprotamex/flavourzyme. Furthermore， the electronic tongue system could distinguish the taste difference of different hydrolysates. Conclusion: The hydrolysis of protamex/flavourzyme can release the umami compounds in the pileus and stipe of Hypsizygus marmoreus more effectively， and the pileus of Hypsizygus marmoreus has greater potential than the stipe in developing flavoring with salt-less condiment.