AbstractThis study investigated the changes in physicochemical and functional properties of water-soluble protein from mussels (MWP) induced by high-pressure homogenization (HPH). The results indicated that HPH treatment unfolded or disrupted the initial structure of MWP, exposing free sulfhydryl groups and buried hydrophobic groups. As the homogenization pressure increased, the aggregation of MWP particles gradually decreased. Moreover, protein solubility and dispersion stability increased in aqueous solution. Foaming and emulsifying properties were also improved. HPH treatment has proven to be an effective technique for enhancing the functional properties of shellfish protein, and 120 MPa was the optimum homogenization pressure to modify MWP.