Two-dimensional gel electrophoresis (2-DE} is a unique method of large-scale protein characterisation, and is a powerful approach in the study of protein expression. In the present work, the experimental conditions for 2-DE of foot proteins from the mussel Mytilus galloprovincialis Lmk were established; the technique was performed with intertidal and cultured mussels using Melanie 3 software for data analysis. This powerful technique enabled the visualisation of a total of 150 protein spots consistently expressed in the foot