Abstract:Traditional method for deproteinizing crab shell consumes a large amount of sodium hydroxide solution，which brings about enviroment pollution.For developing an alternative method，the deproteinization of crab shell by protease was investigated in this paper，with crab shell powder as raw material and deproteinization rate as main evaluating indicator.oteinization experiment was conducted using different kinds of protease，The results showed that alkaline protease is suitable for the deproteinization of crab shell.The optimal deproteinization conditions were obtained as follows：addition amount of alkaline protease，4 U/mg；mesh number of crab shell，160；reaction temperature，45℃；incubation time，4 h；pH，10.5.In this condition，the deproteinization rate of crab shell powder was 78.54%.Therefore，alkaline protease treatment is an effective method for removing protein from crab shell.