A crude protease(CP)was prepared from Aspergillus oryzae in this work.CP,four commercial proteases(Protamex,Papain,PTN6.0S,Flavorzyme)and nonprotease were employed to hydrolyze Pinctada martensi.CP was found to be more effective protease with protein recovery of 68.36% than the tested commercial proteases,just little lower than PTN6.0(71.38%).Moreover,CP produced the highest degree of hydrolysis(DH,64.27%)than others.The test of molecular weight distribution indicated that CP hydrolysate was mainly consisted of <3 ku fraction,especially <1 ku fraction(84.65%) was observed to be the highest of commercial hydrolysates.CP hydrolysate possessed a higher umami amino acid(38.27%) than other hydrolysates so the sensory taste evaluation showed that CP hydrolysate had better taste than other hydrolysates.