The localized electrochemical characteristics of the anodic metal within a zinc/steel couple immersed in seawater was investigated using an Wire Beam Electrode(WBE) composed of 9 zinc wire sensors together with 112 mild steel ones. The results showed that potential and current density distributions of zinc wires were inhomogeneous; main anodic area transferred from the zinc wires adjacent to steel wires to those farther away from zinc/steel interface gradually; besides, some zinc wires behaved as secondary cathodes. This electrochemical inhomogeneity of zinc might mainly be ascribed to the dissimilar distance between zinc and mild steel wire sensors, and their surface electrochemical state as well.