Abstract: The effect of pH on digestive enzyme activity (protease, amylase, lipase) of alimentary organs (hepatopancreas，stomach，gut ) in yellowfin black porgy (Sparus latus) was studied in this paper. The specific activity of protease at different pH shows that the optimum pH for protease in yellowfin black porgy were 2.8，7.0 and 7.4 in stomach, hepatopancreas and intestinal canal, respectively. The optimum pH for lipase in yellowfin black porgy were 7.6，7.2 and 7.6 in stomach, hepatopancreas and intestinal canal, respectively. The optimum pH for amylase in yellowfin black porgy were were 5.2，4.8 and 6.8 in stomach, hepatopancreas and intestinal canal, respectively.