The amylase and algalase of the Pacif ic abalone (Haliotis discus hannai) wer e measured during the length of 2 -3 cm by means of spect rophotome ter .The optimum tempe ratures f or amylase and algalase were 30 ℃ and 35 ℃, The opt imum pH values were 6 .24 and 7 .19 .Under the opt imum temper ature the act ive energy of two enzymes were 5 . 03 ×104 J/mol and 1 .33 ×104 J/mol r espect ively ;the act ivi ty of amylase and algalase were detected when eleven metal ions existed .The resul ts indicated that Cu2 + 、Hg2 、Ag 、Pb2 significantly inhibited the act ivi ty of amylase , and other metal ions activated the activity of amylase .Mn2 , Ba2 and Ca2 can act iva te the amylase two t imes of that in cont rol group .For the algalase , Zn2 , Ag , Hg2 , Li2 and Ba2 significant ly inhibited its activi ty , and the other metal ions had no effects on the algalase .