Titanium and its alloys, possessing high resistance against corrosion, are being specially adopted in a modern salt producing plant for an evaporator, which however could cause a galvanic attack against conventional materials within the plant due to insufficient insulation. This study investigated the electrochemical properties of titanium and Monel, an example of a less noble metal, in a salt-producing environment.Monel showed stable corrosion potential and relatively small anodic polarization resistance while the corrosion potential of titanium became gradually nobler with immersion time.The potential difference between titanium and Monel reached about 0.4 V after 5 days.The apparent cathodic polarization resistance for titanium increased slightly with immersion time, though the potential rage in which cathodic current appeared was extended.The cathodic current density on titanium held at constant potential was increased when the boiling solution under reduced pressure was exposed to air.Similarly the galvanic current between titanium and Monel responded to a smaller value of atmosphere in the brine under reduced pressure and a larger value when exposed to air.The galvanic current was controlled by the cathodic polarization resistance and increased as the area ratio of cathode against anodic increased. The recommended value of insulation resistance was calculated based on an equivalent circuit.