Abstract: Founctional properties of solubility,hydrophilic and lipophilic ability,viscosity,and antioxidant activity of protein hydrolysates from spanish mackerel were investigated in this paper. The results showed that when spanish mackerel protein was hydrolyzed by papain( DH 25 %), high solubility of the hydrolysates was observed within p H range of 3.0 ~11.0( TCA-NSI was between 46.0% and 76.8%), most fractions Mw of hydrlysates were lower than 1350 u,but hydrophilic and lipophilic ability were all reduced,due to the high degree of hydrolysis and digestion characterization of papain,foaming ability and foaming stability of mackerel protein hydrolyzates was undesirable. It was observed that hydrolates had high protein content(10~80mg/m L)and low viscosity which was of 1.14 ~1.82mm2/s of kinematic viscosity under 20℃. It was provided that mackerel protein hydrolyzate had good reducing power,free radical scavenging and anti-lipid peroxidation,the antioxidant capacity increased with the increase of hydrolysate concentration in a dose-effect relationship. The research of this paper about the functional properties of protein hydrolyzates from spanish mackerel would be useful for providing technical support on its application in food processing.